Modify AVR audioplayer code to play random track - c

I have been playing around with ATtiny's and arduino for a while but am a complete newbee in 'real' AVR programming.
I am building a laser gun and target for my son and want to have the target play a random silly animal sound whenever it is hit.
The other functions of the target is maintained by Attiny85s and i therefore stumbled upon Elm-Chans code for interfacing a microSD card with Attiny85 and play .wav files by PWM.
However the code is written so that it plays files on the SD card root folder (or other dir) in order and skips to next in response to a pushbutton on one of the pins.
What i want it to do is to pick and play a random file from the root when button is pushed (i.e. target is hit).
It should play the sound only once and preferably interrupt an already playing file and play another if the target is hit again before the sound has ended.
I have been trying really hard to figure out what to change in the code but come to realize that i need to start from the beginning with learning AVR programming from scratch...however that will take some time and before i get there i humbly hope that any of you could grant me a quick fix and tell me what to do, so i can finish the toy.
Kind regards
Mads
/*----------------------------------------------------------------------------/
/ 8-pin SD audio player R0.05d (C)ChaN, 2011 /
/-----------------------------------------------------------------------------/
/ This project, program codes and circuit diagrams, is opened under license
/ policy of following trems.
/
/ Copyright (C) 2010, ChaN, all right reserved.
/
/ * This project is a free software and there is NO WARRANTY.
/ * No restriction on use. You can use, modify and redistribute it for
/ personal, non-profit or commercial use UNDER YOUR RESPONSIBILITY.
/ * Redistributions of source code must retain the above copyright notice.
/
/----------------------------------------------------------------------------*/
#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/sleep.h>
#include <avr/wdt.h>
#include <string.h>
#include "pff.h"
#include "xitoa.h"
#ifndef MODE
#error Wrong make file.
#endif
#if MODE == 0 /* Single output */
FUSES = {0xE1, 0xDD, 0xFF}; /* Fuse bytes for mono: Low, High and Extended */
#else /* Dual output */
FUSES = {0xE1, 0x7D, 0xFF}; /* Fuse bytes for stereo and mono-HR: Low, High and Extended (*HVS mode only*) */
#endif
/* This is the fuse settings of this project. The fuse data will be included
in the output hex file with program code. However some old flash programmers
cannot load the fuse bits from hex file. If it is the case, remove this line
and use these values to program the fuse bits. */
#define FCC(c1,c2,c3,c4) (((DWORD)c4<<24)+((DWORD)c3<<16)+((WORD)c2<<8)+(BYTE)c1) /* FourCC */
void delay_us (WORD); /* Defined in asmfunc.S */
/*---------------------------------------------------------*/
/* Work Area */
/*---------------------------------------------------------*/
volatile BYTE FifoRi, FifoWi, FifoCt; /* FIFO controls */
BYTE Buff[256]; /* Wave output FIFO */
FATFS Fs; /* File system object */
DIR Dir; /* Directory object */
FILINFO Fno; /* File information */
WORD rb; /* Return value. Put this here to avoid avr-gcc's bug */
/*---------------------------------------------------------*/
static
DWORD load_header (void) /* 0:Invalid format, 1:I/O error, >=1024:Number of samples */
{
DWORD sz, f;
BYTE b, al = 0;
if (pf_read(Buff, 12, &rb)) return 1; /* Load file header (12 bytes) */
if (rb != 12 || LD_DWORD(Buff+8) != FCC('W','A','V','E')) return 0;
for (;;) {
wdt_reset();
pf_read(Buff, 8, &rb); /* Get Chunk ID and size */
if (rb != 8) return 0;
sz = LD_DWORD(&Buff[4]); /* Chunk size */
switch (LD_DWORD(&Buff[0])) { /* Switch by chunk ID */
case FCC('f','m','t',' ') : /* 'fmt ' chunk */
if (sz & 1) sz++; /* Align chunk size */
if (sz > 100 || sz < 16) return 0; /* Check chunk size */
pf_read(Buff, sz, &rb); /* Get content */
if (rb != sz) return 0;
if (Buff[0] != 1) return 0; /* Check coding type (LPCM) */
b = Buff[2];
if (b != 1 && b != 2) return 0; /* Check channels (1/2) */
GPIOR0 = al = b; /* Save channel flag */
b = Buff[14];
if (b != 8 && b != 16) return 0; /* Check resolution (8/16 bit) */
GPIOR0 |= b; /* Save resolution flag */
if (b & 16) al <<= 1;
f = LD_DWORD(&Buff[4]); /* Check sampling freqency (8k-48k) */
if (f < 8000 || f > 48000) return 4;
OCR0A = (BYTE)(F_CPU / 8 / f) - 1; /* Set sampling interval */
break;
case FCC('d','a','t','a') : /* 'data' chunk */
if (!al) return 0; /* Check if format is valid */
if (sz < 1024 || (sz & (al - 1))) return 0; /* Check size */
if (Fs.fptr & (al - 1)) return 0; /* Check word alignment */
return sz; /* Start to play */
case FCC('D','I','S','P') : /* 'DISP' chunk */
case FCC('L','I','S','T') : /* 'LIST' chunk */
case FCC('f','a','c','t') : /* 'fact' chunk */
if (sz & 1) sz++; /* Align chunk size */
pf_lseek(Fs.fptr + sz); /* Skip this chunk */
break;
default : /* Unknown chunk */
return 0;
}
}
return 0;
}
static
void ramp (
int dir /* 0:Ramp-down, 1:Ramp-up */
)
{
#if MODE != 3
BYTE v, d, n;
if (dir) {
v = 0; d = 1;
} else {
v = 128; d = (BYTE)-1;
}
n = 128;
do {
v += d;
OCR1A = v; OCR1B = v;
delay_us(100);
} while (--n);
#else
dir = dir ? 128 : 0;
OCR1A = (BYTE)dir; OCR1B = (BYTE)dir;
#endif
}
static
FRESULT play (
const char *dir, /* Directory */
const char *fn /* File */
)
{
DWORD sz;
FRESULT res;
BYTE sw;
WORD btr;
wdt_reset();
xsprintf((char*)Buff, PSTR("%s/%s"), dir, fn);
res = pf_open((char*)Buff); /* Open sound file */
if (res == FR_OK) {
sz = load_header(); /* Check file format and ready to play */
if (sz < 1024) return 255; /* Cannot play this file */
FifoCt = 0; FifoRi = 0; FifoWi = 0; /* Reset audio FIFO */
if (!TCCR1) { /* Enable audio out if not enabled */
PLLCSR = 0b00000110; /* Select PLL clock for TC1.ck */
GTCCR = 0b01100000; /* Enable OC1B as PWM */
TCCR1 = MODE ? 0b01100001 : 0b00000001; /* Start TC1 and enable OC1A as PWM if needed */
TCCR0A = 0b00000010; /* Statr TC0 as interval timer at 2MHz */
TCCR0B = 0b00000010;
TIMSK = _BV(OCIE0A);
ramp(1);
}
pf_read(0, 512 - (Fs.fptr % 512), &rb); /* Snip sector unaligned part */
sz -= rb;
sw = 1; /* Button status flag */
do { /* Data transfer loop */
wdt_reset();
btr = (sz > 1024) ? 1024 : (WORD)sz;/* A chunk of audio data */
res = pf_read(0, btr, &rb); /* Forward the data into audio FIFO */
if (rb != 1024) break; /* Break on error or end of data */
sz -= rb; /* Decrease data counter */
sw <<= 1; /* Break on button down */
} while ((PINB & 1) || ++sw != 1);
}
while (FifoCt) ; /* Wait for audio FIFO empty */
OCR1A = 128; OCR1B = 128; /* Return output to center level */
return res;
}
static
void delay500 (void)
{
wdt_reset();
TCCR0B = 0; TCCR0A = 0; /* Stop TC0 */
if (TCCR1) { /* Stop TC1 if enabled */
ramp(0);
TCCR1 = 0; GTCCR = 0;
}
WDTCR = _BV(WDE) | _BV(WDIE) | 0b101; /* Set WDT to interrupt mode in timeout of 0.5s */
set_sleep_mode(SLEEP_MODE_PWR_DOWN); /* Enter power down mode */
sleep_mode();
wdt_reset();
WDTCR = _BV(WDE) | 0b110; /* Set WDT to reset mode in timeout of 1s */
}
EMPTY_INTERRUPT(WDT_vect);
/*-----------------------------------------------------------------------*/
/* Main */
int main (void)
{
FRESULT res;
char *dir;
BYTE org_osc = OSCCAL;
MCUSR = 0;
WDTCR = _BV(WDE) | 0b110; /* Enable WDT reset in timeout of 1s */
PORTB = 0b101001; /* Initialize port: - - H L H L L P */
DDRB = 0b111110;
sei();
for (;;) {
if (pf_mount(&Fs) == FR_OK) { /* Initialize FS */
wdt_reset();
Buff[0] = 0;
if (!pf_open("osccal")) pf_read(Buff, 1, &rb); /* Adjust frequency */
OSCCAL = org_osc + Buff[0];
res = pf_opendir(&Dir, dir = "wav"); /* Open sound file directory */
if (res == FR_NO_PATH)
res = pf_opendir(&Dir, dir = ""); /* Open root directory */
while (res == FR_OK) { /* Repeat in the dir */
res = pf_readdir(&Dir, 0); /* Rewind dir */
while (res == FR_OK) { /* Play all wav files in the dir */
wdt_reset();
res = pf_readdir(&Dir, &Fno); /* Get a dir entry */
if (res || !Fno.fname[0]) break; /* Break on error or end of dir */
if (!(Fno.fattrib & (AM_DIR|AM_HID)) && strstr(Fno.fname, ".WAV"))
res = play(dir, Fno.fname); /* Play file */
}
}
}
delay500(); /* Delay 500ms in low power sleep mode */
}
}

I reckon your case requires more C-coding knowledge than AVR-hacking one.
Here:
if (!(Fno.fattrib & (AM_DIR|AM_HID)) && strstr(Fno.fname, ".WAV"))
res = play(dir, Fno.fname); /* Play file */
Every time matching file is found, play function is called. What you want instead is to add this file descriptor to some form of container (e.g. list) of available files. After all files are listed, you may want to wait for external input (hit by laser), and then play the file and move current file index to the next.
To enable pausing and resetting playback, I recommend using external interrupt for handling "on hit" events.
PS Building toys for your kid using AVR? +1 from me!

Related

How to implement poll function into Linux kernel module?

I'm trying to implement polling functionality into my simple Linux kernel module called gpio_driver for my Raspberry Pi which should notify the user space poll function about the change of state of one of the GPIO pins (button push).
What I did in my gpio_driver is set the internal pull down on my GPIO_04 pin and direction to input, so when I press the button connected to the pin on one side and +5V on the other, it should generate a pulse which should notify the user space poll function that the button push happened and end the user space program.
The user space program code:
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/time.h>
#include <poll.h>
int main(int argc, char *argv[])
{
char str[256];
struct pollfd pfd;
int fd, gpio;
char buf[8];
sprintf(str, "/dev/gpio_driver");
if ((fd = open(str, O_RDONLY)) < 0)
{
fprintf(stderr, "Failed, gpio %d not exported.\n", gpio);
exit(1);
}
pfd.fd = fd;
pfd.events = POLLPRI;
lseek(fd, 0, SEEK_SET); /* consume any prior interrupt */
read(fd, buf, sizeof buf);
poll(&pfd, 1, -1); /* wait for interrupt */
lseek(fd, 0, SEEK_SET); /* consume interrupt */
read(fd, buf, sizeof buf);
exit(0);
}
Complete driver code (poll function implementation at the end of file):
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/proc_fs.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/ktime.h>
#include <linux/hrtimer.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/uaccess.h>
#include <linux/ioctl.h>
#include <linux/poll.h>
MODULE_LICENSE("Dual BSD/GPL");
/* if defined, timer callback will implement LED0 flashing and
SW0 reading after each interval */
#define TEST
// timer interval defined as (TIMER_SEC + TIMER_NANO_SEC)
#define TIMER_SEC 0
#define TIMER_NANO_SEC 250*1000*1000 /* 250ms */
// NOTE: Check Broadcom BCM8325 datasheet, page 91+
// NOTE: GPIO Base address is set to 0x7E200000,
// but it is VC CPU BUS address, while the
// ARM physical address is 0x3F200000, what
// can be seen in pages 5-7 of Broadcom
// BCM8325 datasheet, having in mind that
// total system ram is 0x3F000000 (1GB - 16MB)
// instead of 0x20000000 (512 MB)
/* GPIO registers base address. */
#define BCM2708_PERI_BASE (0x3F000000)
#define GPIO_BASE (BCM2708_PERI_BASE + 0x200000)
#define GPIO_ADDR_SPACE_LEN (0xB4)
//--
//Handle GPIO: 0-9
/* GPIO Function Select 0. */
#define GPFSEL0_OFFSET (0x00000000)
//Handle GPIO: 10-19
/* GPIO Function Select 1. */
#define GPFSEL1_OFFSET (0x00000004)
//Handle GPIO: 20-29
/* GPIO Function Select 2. */
#define GPFSEL2_OFFSET (0x00000008)
//Handle GPIO: 30-39
/* GPIO Function Select 3. */
#define GPFSEL3_OFFSET (0x0000000C)
//Handle GPIO: 40-49
/* GPIO Function Select 4. */
#define GPFSEL4_OFFSET (0x00000010)
//Handle GPIO: 50-53
/* GPIO Function Select 5. */
#define GPFSEL5_OFFSET (0x00000014)
//--
//GPIO: 0-31
/* GPIO Pin Output Set 0. */
#define GPSET0_OFFSET (0x0000001C)
//GPIO: 32-53
/* GPIO Pin Output Set 1. */
#define GPSET1_OFFSET (0x00000020)
//--
//GPIO: 0-31
/* GPIO Pin Output Clear 0. */
#define GPCLR0_OFFSET (0x00000028)
//GPIO: 32-53
/* GPIO Pin Output Clear 1. */
#define GPCLR1_OFFSET (0x0000002C)
//--
//GPIO: 0-31
/* GPIO Pin Level 0. */
#define GPLEV0_OFFSET (0x00000034)
//GPIO: 32-53
/* GPIO Pin Level 1. */
#define GPLEV1_OFFSET (0x00000038)
//--
//GPIO: 0-53
/* GPIO Pin Pull-up/down Enable. */
#define GPPUD_OFFSET (0x00000094)
//GPIO: 0-31
/* GPIO Pull-up/down Clock Register 0. */
#define GPPUDCLK0_OFFSET (0x00000098)
//GPIO: 32-53
/* GPIO Pull-up/down Clock Register 1. */
#define GPPUDCLK1_OFFSET (0x0000009C)
//--
/* PUD - GPIO Pin Pull-up/down */
typedef enum {PULL_NONE = 0, PULL_DOWN = 1, PULL_UP = 2} PUD;
//--
//000 = GPIO Pin 'x' is an input
//001 = GPIO Pin 'x' is an output
// By default GPIO pin is being used as an input
typedef enum {GPIO_DIRECTION_IN = 0, GPIO_DIRECTION_OUT = 1} DIRECTION;
//--
/* GPIO pins available on connector p1. */
#define GPIO_02 (2)
#define GPIO_03 (3)
#define GPIO_04 (4)
#define GPIO_05 (5)
#define GPIO_06 (6)
#define GPIO_07 (7)
#define GPIO_08 (8)
#define GPIO_09 (9)
#define GPIO_10 (10)
#define GPIO_11 (11)
#define GPIO_12 (12)
#define GPIO_13 (13)
#define GPIO_14 (14)
#define GPIO_15 (15)
#define GPIO_16 (16)
#define GPIO_17 (17)
#define GPIO_18 (18)
#define GPIO_19 (19)
#define GPIO_20 (20)
#define GPIO_21 (21)
#define GPIO_22 (22)
#define GPIO_23 (23)
#define GPIO_24 (24)
#define GPIO_25 (25)
#define GPIO_26 (26)
#define GPIO_27 (27)
/* Declaration of gpio_driver.c functions */
int gpio_driver_init(void);
void gpio_driver_exit(void);
static int gpio_driver_open(struct inode *, struct file *);
static int gpio_driver_release(struct inode *, struct file *);
static ssize_t gpio_driver_read(struct file *, char *buf, size_t , loff_t *);
static ssize_t gpio_driver_write(struct file *, const char *buf, size_t , loff_t *);
static unsigned int gpio_driver_poll(struct file *, poll_table *);
/* Structure that declares the usual file access functions. */
struct file_operations gpio_driver_fops =
{
open : gpio_driver_open,
release : gpio_driver_release,
read : gpio_driver_read,
write : gpio_driver_write,
poll : gpio_driver_poll
};
static DECLARE_WAIT_QUEUE_HEAD(gpio_driver_wait);
/* Declaration of the init and exit functions. */
module_init(gpio_driver_init);
module_exit(gpio_driver_exit);
/* Major number. */
int gpio_driver_major;
/* Buffer to store data. */
#define BUF_LEN 80
char* gpio_driver_buffer;
/* Virtual address where the physical GPIO address is mapped */
void* virt_gpio_base;
/*
* GetGPFSELReg function
* Parameters:
* pin - number of GPIO pin;
*
* return - GPFSELn offset from GPIO base address, for containing desired pin control
* Operation:
* Based on the passed GPIO pin number, finds the corresponding GPFSELn reg and
* returns its offset from GPIO base address.
*/
unsigned int GetGPFSELReg(char pin)
{
unsigned int addr;
if(pin >= 0 && pin <10)
addr = GPFSEL0_OFFSET;
else if(pin >= 10 && pin <20)
addr = GPFSEL1_OFFSET;
else if(pin >= 20 && pin <30)
addr = GPFSEL2_OFFSET;
else if(pin >= 30 && pin <40)
addr = GPFSEL3_OFFSET;
else if(pin >= 40 && pin <50)
addr = GPFSEL4_OFFSET;
else /*if(pin >= 50 && pin <53) */
addr = GPFSEL5_OFFSET;
return addr;
}
/*
* GetGPIOPinOffset function
* Parameters:
* pin - number of GPIO pin;
*
* return - offset of the pin control bit, position in control registers
* Operation:
* Based on the passed GPIO pin number, finds the position of its control bit
* in corresponding control registers.
*/
char GetGPIOPinOffset(char pin)
{
if(pin >= 0 && pin <10)
pin = pin;
else if(pin >= 10 && pin <20)
pin -= 10;
else if(pin >= 20 && pin <30)
pin -= 20;
else if(pin >= 30 && pin <40)
pin -= 30;
else if(pin >= 40 && pin <50)
pin -= 40;
else /*if(pin >= 50 && pin <53) */
pin -= 50;
return pin;
}
/*
* SetInternalPullUpDown function
* Parameters:
* pin - number of GPIO pin;
* pull - set internal pull up/down/none if PULL_UP/PULL_DOWN/PULL_NONE selected
* Operation:
* Sets to use internal pull-up or pull-down resistor, or not to use it if pull-none
* selected for desired GPIO pin.
*/
void SetInternalPullUpDown(char pin, PUD pull)
{
unsigned int gppud_offset;
unsigned int gppudclk_offset;
unsigned int tmp;
unsigned int mask;
/* Get the offset of GPIO Pull-up/down Register (GPPUD) from GPIO base address. */
gppud_offset = GPPUD_OFFSET;
/* Get the offset of GPIO Pull-up/down Clock Register (GPPUDCLK) from GPIO base address. */
gppudclk_offset = (pin < 32) ? GPPUDCLK0_OFFSET : GPPUDCLK1_OFFSET;
/* Get pin offset in register . */
pin = (pin < 32) ? pin : pin - 32;
/* Write to GPPUD to set the required control signal (i.e. Pull-up or Pull-Down or neither
to remove the current Pull-up/down). */
iowrite32(pull, virt_gpio_base + gppud_offset);
/* Wait 150 cycles – this provides the required set-up time for the control signal */
/* Write to GPPUDCLK0/1 to clock the control signal into the GPIO pads you wish to
modify – NOTE only the pads which receive a clock will be modified, all others will
retain their previous state. */
tmp = ioread32(virt_gpio_base + gppudclk_offset);
mask = 0x1 << pin;
tmp |= mask;
iowrite32(tmp, virt_gpio_base + gppudclk_offset);
/* Wait 150 cycles – this provides the required hold time for the control signal */
/* Write to GPPUD to remove the control signal. */
iowrite32(PULL_NONE, virt_gpio_base + gppud_offset);
/* Write to GPPUDCLK0/1 to remove the clock. */
tmp = ioread32(virt_gpio_base + gppudclk_offset);
mask = 0x1 << pin;
tmp &= (~mask);
iowrite32(tmp, virt_gpio_base + gppudclk_offset);
}
/*
* SetGpioPinDirection function
* Parameters:
* pin - number of GPIO pin;
* direction - GPIO_DIRECTION_IN or GPIO_DIRECTION_OUT
* Operation:
* Sets the desired GPIO pin to be used as input or output based on the direcation value.
*/
void SetGpioPinDirection(char pin, DIRECTION direction)
{
unsigned int GPFSELReg_offset;
unsigned int tmp;
unsigned int mask;
/* Get base address of function selection register. */
GPFSELReg_offset = GetGPFSELReg(pin);
/* Calculate gpio pin offset. */
pin = GetGPIOPinOffset(pin);
/* Set gpio pin direction. */
tmp = ioread32(virt_gpio_base + GPFSELReg_offset);
if(direction)
{ //set as output: set 1
mask = 0x1 << (pin*3);
tmp |= mask;
}
else
{ //set as input: set 0
mask = ~(0x1 << (pin*3));
tmp &= mask;
}
iowrite32(tmp, virt_gpio_base + GPFSELReg_offset);
}
/*
* GetGpioPinDirection function
* Parameters:
* pin - number of GPIO pin;
* Operation:
* Gets the desired GPIO pin's direction and returns 0 for IN and 1 for OUT.
*/
int GetGpioPinDirection(char pin)
{
unsigned int GPFSELReg_offset;
unsigned int tmp;
unsigned int mask;
/* Get base address of function selection register. */
GPFSELReg_offset = GetGPFSELReg(pin);
/* Calculate gpio pin offset. */
pin = GetGPIOPinOffset(pin);
/* Get gpio pin direction. */
tmp = ioread32(virt_gpio_base + GPFSELReg_offset);
mask = 0x1 << (pin*3);
tmp &= mask;
tmp=tmp>>(pin*3);
return tmp;
}
/*
* SetGpioPin function
* Parameters:
* pin - number of GPIO pin;
* Operation:
* Sets the desired GPIO pin to HIGH level. The pin should previously be defined as output.
*/
void SetGpioPin(char pin)
{
unsigned int GPSETreg_offset;
unsigned int tmp;
/* Get base address of gpio set register. */
GPSETreg_offset = (pin < 32) ? GPSET0_OFFSET : GPSET1_OFFSET;
pin = (pin < 32) ? pin : pin - 32;
/* Set gpio. */
tmp = 0x1 << pin;
iowrite32(tmp, virt_gpio_base + GPSETreg_offset);
}
/*
* ClearGpioPin function
* Parameters:
* pin - number of GPIO pin;
* Operation:
* Sets the desired GPIO pin to LOW level. The pin should previously be defined as output.
*/
void ClearGpioPin(char pin)
{
unsigned int GPCLRreg_offset;
unsigned int tmp;
/* Get base address of gpio clear register. */
GPCLRreg_offset = (pin < 32) ? GPCLR0_OFFSET : GPCLR1_OFFSET;
pin = (pin < 32) ? pin : pin - 32;
/* Clear gpio. */
tmp = 0x1 << pin;
iowrite32(tmp, virt_gpio_base + GPCLRreg_offset);
}
/*
* GetGpioPinValue function
* Parameters:
* pin - number of GPIO pin;
*
* return - the level read from desired GPIO pin
* Operation:
* Reads the level from the desired GPIO pin and returns the read value.
*/
char GetGpioPinValue(char pin)
{
unsigned int GPLEVreg_offset;
unsigned int tmp;
unsigned int mask;
/* Get base address of gpio level register. */
GPLEVreg_offset = (pin < 32) ? GPLEV0_OFFSET : GPLEV1_OFFSET;
pin = (pin < 32) ? pin : pin - 32;
/* Read gpio pin level. */
tmp = ioread32(virt_gpio_base + GPLEVreg_offset);
mask = 0x1 << pin;
tmp &= mask;
return (tmp >> pin);
}
/*
* Initialization:
* 1. Register device driver
* 2. Allocate buffer
* 3. Initialize buffer
* 4. Map GPIO Physical address space to virtual address
* 5. Initialize GPIO pin
*/
int gpio_driver_init(void)
{
int result = -1;
printk(KERN_INFO "Inserting gpio_driver module\n");
/* Registering device. */
result = register_chrdev(0, "gpio_driver", &gpio_driver_fops);
if (result < 0)
{
printk(KERN_INFO "gpio_driver: cannot obtain major number %d\n", gpio_driver_major);
return result;
}
gpio_driver_major = result;
printk(KERN_INFO "gpio_driver major number is %d\n", gpio_driver_major);
/* Allocating memory for the buffer. */
gpio_driver_buffer = kmalloc(BUF_LEN, GFP_KERNEL);
if (!gpio_driver_buffer)
{
result = -ENOMEM;
goto fail_no_mem;
}
/* Initialize data buffer. */
memset(gpio_driver_buffer, 0, BUF_LEN);
/* map the GPIO register space from PHYSICAL address space to virtual address space */
virt_gpio_base = ioremap(GPIO_BASE, GPIO_ADDR_SPACE_LEN);
if(!virt_gpio_base)
{
result = -ENOMEM;
goto fail_no_virt_mem;
}
/* Initialize GPIO pin. */
SetGpioPinDirection(GPIO_04, GPIO_DIRECTION_IN);
SetInternalPullUpDown(GPIO_04, PULL_DOWN); // rising edge
return 0;
fail_no_virt_mem:
/* Freeing buffer gpio_driver_buffer. */
if (gpio_driver_buffer)
{
kfree(gpio_driver_buffer);
}
fail_no_mem:
/* Freeing the major number. */
unregister_chrdev(gpio_driver_major, "gpio_driver");
return result;
}
/*
* Cleanup:
* 1. stop the timer
* 2. release GPIO pins (clear all outputs, set all as inputs and pull-none to minimize the power consumption)
* 3. Unmap GPIO Physical address space from virtual address
* 4. Free buffer
* 5. Unregister device driver
*/
void gpio_driver_exit(void)
{
printk(KERN_INFO "Removing gpio_driver module..\n");
/* Clear GPIO pins. */
ClearGpioPin(GPIO_04);
/* Set GPIO pins as inputs and disable pull-ups. */
SetGpioPinDirection(GPIO_04, GPIO_DIRECTION_IN);
SetInternalPullUpDown(GPIO_04, PULL_NONE);
/* Unmap GPIO Physical address space. */
if (virt_gpio_base)
{
iounmap(virt_gpio_base);
}
/* Freeing buffer gpio_driver_buffer. */
if (gpio_driver_buffer)
{
kfree(gpio_driver_buffer);
}
/* Freeing the major number. */
unregister_chrdev(gpio_driver_major, "gpio_driver");
}
/* File open function. */
static int gpio_driver_open(struct inode *inode, struct file *filp)
{
/* Success. */
return 0;
}
/* File close function. */
static int gpio_driver_release(struct inode *inode, struct file *filp)
{
/* Success. */
return 0;
}
/* File read function */
static ssize_t gpio_driver_read(struct file *filp, char *buf, size_t len, loff_t *f_pos)
{
/* Size of valid data in gpio_driver - data to send in user space. */
int data_size = 0;
/* Copy GPIO pin state to user space. */
gpio_driver_buffer[0]=GetGpioPinValue(GPIO_04);
/* TODO: fill gpio_driver_buffer here. */
if (*f_pos == 0)
{
/* Get size of valid data. */
data_size = strlen(gpio_driver_buffer);
/* Send data to user space. */
if (copy_to_user(buf, gpio_driver_buffer, data_size) != 0)
{
return -EFAULT;
}
else
{
(*f_pos) += data_size;
return data_size;
}
}
else
{
return 0;
}
}
/* File write function */
static ssize_t gpio_driver_write(struct file *filp, const char *buf, size_t len, loff_t *f_pos)
{
printk(KERN_ALERT "Sorry, this operation isn't supported.\n");
return -EPERM; // Operation not permitted error
}
static unsigned int gpio_driver_poll(struct file *filp, poll_table *wait)
{
unsigned int mask = 0;
poll_wait(filp, &gpio_driver_wait, wait);
if(GetGpioPinValue(GPIO_04)!=0)
gpio_driver_buffer[0] = 1;
if(gpio_driver_buffer[0] == 1)
{
mask |= POLLIN | POLLPRI;
wake_up_interruptible(&gpio_driver_wait);
}
gpio_driver_buffer[0] = 0;
return mask;
}
However, when I run my user space program, it doesn't react to my button pushes and it never exits. I'm pretty new to polling all the code written in the driver related to polling and user program I picked up online from different sources and some books (mainly Linux Device Drivers, 3rd edition, chapter 6). What am I doing wrong?

EFM32 Gecko Starter Kit USART1 Receive not working (EFM32G890F128)

I have been trying to setup a uart on the EFM32 Starter kind and I am now able to send characters out of the EFM32 Starter kit board to a computer, but when I try to receive from the computer using the example, my interrupt gets called once, but the data I get is 0x0 and then after the first character I dont receive the interrupt again.
I modified the code from the application note software that can be found on silab's website: USART/UART Asynchronous mode Application Note software
I have added the code to this question as well. Has anyone else encountered this? I must be doing something silly.
I checked the RXDATA register in the debugger and it keeps showing 0 even when I press a the "a" character on the keyboard. Also the interrupt only fires once, with the rxdata being 0, then I never get an interrupt after that.
Thanks in advance.
/******************************************************************************
* #file main.c
* #brief USART/UART Asynchronous mode Application Note software example
* #author Silicon Labs
* #version 1.03
******************************************************************************
* #section License
* <b>(C) Copyright 2014 Silicon Labs, http://www.silabs.com</b>
*******************************************************************************
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*
* DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Silicon Labs has no
* obligation to support this Software. Silicon Labs is providing the
* Software "AS IS", with no express or implied warranties of any kind,
* including, but not limited to, any implied warranties of merchantability
* or fitness for any particular purpose or warranties against infringement
* of any proprietary rights of a third party.
*
* Silicon Labs will not be liable for any consequential, incidental, or
* special damages, or any other relief, or for any claim by any third party,
* arising from your use of this Software.
*
******************************************************************************/
#include <stdint.h>
#include "em_device.h"
#include "em_chip.h"
#include "em_emu.h"
#include "em_cmu.h"
#include "em_gpio.h"
#include "em_usart.h"
#include "bsp.h"
/* Function prototypes */
void uartSetup(void);
void cmuSetup(void);
void uartPutData(uint8_t * dataPtr, uint32_t dataLen);
uint32_t uartGetData(uint8_t * dataPtr, uint32_t dataLen);
void uartPutChar(uint8_t charPtr);
uint8_t uartGetChar(void);
/* Declare some strings */
const char welcomeString[] = "EFM32 RS-232 - Please press a key\r\n";
const char overflowString[] = "\n---RX OVERFLOW---\n";
const uint32_t welLen = sizeof(welcomeString) - 1;
const uint32_t ofsLen = sizeof(overflowString) - 1;
/* Define termination character */
#define TERMINATION_CHAR '.'
/* Declare a circular buffer structure to use for Rx and Tx queues */
#define BUFFERSIZE 256
volatile struct circularBuffer
{
uint8_t data[BUFFERSIZE]; /* data buffer */
uint32_t rdI; /* read index */
uint32_t wrI; /* write index */
uint32_t pendingBytes; /* count of how many bytes are not yet handled */
bool overflow; /* buffer overflow indicator */
} rxBuf, txBuf = { {0}, 0, 0, 0, false };
/* Setup UART1 in async mode for RS232*/
static USART_TypeDef * uart = USART1;
static USART_InitAsync_TypeDef uartInit = USART_INITASYNC_DEFAULT;
/******************************************************************************
* #brief Main function
*
*****************************************************************************/
int main(void)
{
/* Initialize chip - handle erratas */
CHIP_Init( );
/* Initialize clocks and oscillators */
cmuSetup( );
/* Initialize UART peripheral */
uartSetup( );
/* Initialize Development Kit in EBI mode */
// BSP_Init(BSP_INIT_DEFAULT);
/* Enable RS-232 transceiver on Development Kit */
//BSP_PeripheralAccess(BSP_RS232_UART, true);
/* When DVK is configured, and no more DVK access is needed, the interface can safely be disabled to save current */
//BSP_Disable();
/* Write welcome message to UART */
uartPutData((uint8_t*) welcomeString, welLen);
/* Eternal while loop
* CPU will sleep during Rx and Tx. When a byte is transmitted, an interrupt
* wakes the CPU which copies the next byte in the txBuf queue to the
* UART TXDATA register.
*
* When the predefined termiation character is received, the all pending
* data in rxBuf is copied to txBuf and echoed back on the UART */
while (1)
{
/* Wait in EM1 while UART transmits */
EMU_EnterEM1();
/* Check if RX buffer has overflowed */
if (rxBuf.overflow)
{
rxBuf.overflow = false;
uartPutData((uint8_t*) overflowString, ofsLen);
}
/* Check if termination character is received */
if (rxBuf.data[(rxBuf.wrI - 1) % BUFFERSIZE] == TERMINATION_CHAR)
{
/* Copy received data to UART transmit queue */
uint8_t tmpBuf[BUFFERSIZE];
int len = uartGetData(tmpBuf, 0);
uartPutData(tmpBuf, len);
}
}
}
/******************************************************************************
* #brief uartSetup function
*
******************************************************************************/
void uartSetup(void)
{
/* Enable clock for GPIO module (required for pin configuration) */
CMU_ClockEnable(cmuClock_GPIO, true);
/* Configure GPIO pins */
GPIO_PinModeSet(gpioPortC, 0, gpioModePushPull, 1);
GPIO_PinModeSet(gpioPortC, 1, gpioModeInput, 0);
/* Prepare struct for initializing UART in asynchronous mode*/
uartInit.enable = usartDisable; /* Don't enable UART upon intialization */
uartInit.refFreq = 0; /* Provide information on reference frequency. When set to 0, the reference frequency is */
uartInit.baudrate = 115200; /* Baud rate */
uartInit.oversampling = usartOVS16; /* Oversampling. Range is 4x, 6x, 8x or 16x */
uartInit.databits = usartDatabits8; /* Number of data bits. Range is 4 to 10 */
uartInit.parity = usartNoParity; /* Parity mode */
uartInit.stopbits = usartStopbits1; /* Number of stop bits. Range is 0 to 2 */
// uartInit.mvdis = false; /* Disable majority voting */
// uartInit.prsRxEnable = false; /* Enable USART Rx via Peripheral Reflex System */
// uartInit.prsRxCh = usartPrsRxCh0; /* Select PRS channel if enabled */
/* Initialize USART with uartInit struct */
USART_InitAsync(uart, &uartInit);
/* Prepare UART Rx and Tx interrupts */
USART_IntClear(uart, _UART_IFC_MASK);
USART_IntEnable(uart, UART_IEN_RXDATAV);
NVIC_ClearPendingIRQ(USART1_RX_IRQn);
NVIC_ClearPendingIRQ(USART1_TX_IRQn);
NVIC_EnableIRQ(USART1_RX_IRQn);
NVIC_EnableIRQ(USART1_TX_IRQn);
/* Enable I/O pins at UART1 location #2 */
uart->ROUTE = UART_ROUTE_RXPEN | UART_ROUTE_TXPEN | UART_ROUTE_LOCATION_LOC0;
/* Enable UART */
USART_Enable(uart, usartEnable);
}
/******************************************************************************
* #brief uartGetChar function
*
* Note that if there are no pending characters in the receive buffer, this
* function will hang until a character is received.
*
*****************************************************************************/
uint8_t uartGetChar( )
{
uint8_t ch;
/* Check if there is a byte that is ready to be fetched. If no byte is ready, wait for incoming data */
if (rxBuf.pendingBytes < 1)
{
while (rxBuf.pendingBytes < 1) ;
}
/* Copy data from buffer */
ch = rxBuf.data[rxBuf.rdI];
rxBuf.rdI = (rxBuf.rdI + 1) % BUFFERSIZE;
/* Decrement pending byte counter */
rxBuf.pendingBytes--;
return ch;
}
/******************************************************************************
* #brief uartPutChar function
*
*****************************************************************************/
void uartPutChar(uint8_t ch)
{
/* Check if Tx queue has room for new data */
if ((txBuf.pendingBytes + 1) > BUFFERSIZE)
{
/* Wait until there is room in queue */
while ((txBuf.pendingBytes + 1) > BUFFERSIZE) ;
}
/* Copy ch into txBuffer */
txBuf.data[txBuf.wrI] = ch;
txBuf.wrI = (txBuf.wrI + 1) % BUFFERSIZE;
/* Increment pending byte counter */
txBuf.pendingBytes++;
/* Enable interrupt on USART TX Buffer*/
USART_IntEnable(uart, UART_IEN_TXBL);
}
/******************************************************************************
* #brief uartPutData function
*
*****************************************************************************/
void uartPutData(uint8_t * dataPtr, uint32_t dataLen)
{
uint32_t i = 0;
/* Check if buffer is large enough for data */
if (dataLen > BUFFERSIZE)
{
/* Buffer can never fit the requested amount of data */
return;
}
/* Check if buffer has room for new data */
if ((txBuf.pendingBytes + dataLen) > BUFFERSIZE)
{
/* Wait until room */
while ((txBuf.pendingBytes + dataLen) > BUFFERSIZE) ;
}
/* Fill dataPtr[0:dataLen-1] into txBuffer */
while (i < dataLen)
{
txBuf.data[txBuf.wrI] = *(dataPtr + i);
txBuf.wrI = (txBuf.wrI + 1) % BUFFERSIZE;
i++;
}
/* Increment pending byte counter */
txBuf.pendingBytes += dataLen;
/* Enable interrupt on USART TX Buffer*/
USART_IntEnable(uart, UART_IEN_TXBL);
}
/******************************************************************************
* #brief uartGetData function
*
*****************************************************************************/
uint32_t uartGetData(uint8_t * dataPtr, uint32_t dataLen)
{
uint32_t i = 0;
/* Wait until the requested number of bytes are available */
if (rxBuf.pendingBytes < dataLen)
{
while (rxBuf.pendingBytes < dataLen) ;
}
if (dataLen == 0)
{
dataLen = rxBuf.pendingBytes;
}
/* Copy data from Rx buffer to dataPtr */
while (i < dataLen)
{
*(dataPtr + i) = rxBuf.data[rxBuf.rdI];
rxBuf.rdI = (rxBuf.rdI + 1) % BUFFERSIZE;
i++;
}
/* Decrement pending byte counter */
rxBuf.pendingBytes -= dataLen;
return i;
}
/***************************************************************************//**
* #brief Set up Clock Management Unit
******************************************************************************/
void cmuSetup(void)
{
/* Start HFXO and wait until it is stable */
/* CMU_OscillatorEnable( cmuOsc_HFXO, true, true); */
/* Select HFXO as clock source for HFCLK */
/* CMU_ClockSelectSet(cmuClock_HF, cmuSelect_HFXO ); */
/* Disable HFRCO */
/* CMU_OscillatorEnable( cmuOsc_HFRCO, false, false ); */
/* Enable clock for HF peripherals */
CMU_ClockEnable(cmuClock_HFPER, true);
/* Enable clock for USART module */
CMU_ClockEnable(cmuClock_USART1, true);
}
/**************************************************************************//**
* #brief UART1 RX IRQ Handler
*
* Set up the interrupt prior to use
*
* Note that this function handles overflows in a very simple way.
*
*****************************************************************************/
void USART1_RX_IRQHandler(void)
{
/* Check for RX data valid interrupt */
if (uart->IF & UART_IF_RXDATAV)
{
/* Copy data into RX Buffer */
uint8_t rxData = USART_Rx(uart);
rxBuf.data[rxBuf.wrI] = rxData;
rxBuf.wrI = (rxBuf.wrI + 1) % BUFFERSIZE;
rxBuf.pendingBytes++;
/* Flag Rx overflow */
if (rxBuf.pendingBytes > BUFFERSIZE)
{
rxBuf.overflow = true;
}
}
}
/**************************************************************************//**
* #brief UART1 TX IRQ Handler
*
* Set up the interrupt prior to use
*
*****************************************************************************/
void USART1_TX_IRQHandler(void)
{
/* Check TX buffer level status */
if (uart->IF & UART_IF_TXBL)
{
if (txBuf.pendingBytes > 0)
{
/* Transmit pending character */
USART_Tx(uart, txBuf.data[txBuf.rdI]);
txBuf.rdI = (txBuf.rdI + 1) % BUFFERSIZE;
txBuf.pendingBytes--;
}
/* Disable Tx interrupt if no more bytes in queue */
if (txBuf.pendingBytes == 0)
{
USART_IntDisable(uart, UART_IEN_TXBL);
}
}
}

Using FatFs causes infinite loop in f_write on PIC18F46J50 uC

Im trying to implement the FatFs module for a project for several days now.
My low-level I/O configurations are correctly implemented as i can see the signals using an oscilloscope. But i cant seem to get a proper write working on the SD-Card. All i get is an empty file on my SD-Card which gets created correctly. Also a read of the files works just fine. As i was debugging using MPLAB X i found that the f_write function never leaves a for loop.
Here is my main.c code:
/*
Main application
*/
FATFS FatFs;
FIL fil1, fil2;
void main(void)
{
SYSTEM_Init();
BYTE buffer[4];
UINT bw, br;
FRESULT fr;
if(f_mount(&FatFs, "", 1) == FR_OK)
{
//open source file
fr = f_open(&fil1, "READ.TXT", FA_READ);
if(fr) return;
//create destination file
fr = f_open(&fil2, "WRITE.TXT", FA_WRITE | FA_CREATE_ALWAYS);
if(fr) return;
//copy 1 to 2
for(;;){
fr = f_read(&fil1, buffer, sizeof buffer, &br);
if(fr || br == 0) break;
fr = f_write(&fil2, buffer, br, &bw);
if(fr || bw < br) break;
}
// const char *writedata = &write;
// //f_printf(&fil, "%d", 1234);
// f_write(&fil, writedata, strlen(writedata), &bw);
f_close(&fil1);
f_close(&fil2);
f_mount(NULL, "", 0);
}
return;
}
Here is my diskio.c code:
/*-----------------------------------------------------------------------*/
/* Low level disk I/O module skeleton for FatFs (C)ChaN, 2016 */
/*-----------------------------------------------------------------------*/
/* If a working storage control module is available, it should be */
/* attached to the FatFs via a glue function rather than modifying it. */
/* This is an example of glue functions to attach various exsisting */
/* storage control modules to the FatFs module with a defined API. */
/*-----------------------------------------------------------------------*/
#ifdef __XC8
#include <p18f46j50.h>
#endif
#ifndef __XC8
#include <p18cxxx.h>
#endif
#include "diskio.h" /* FatFs lower layer API */
#include "sdspi.h"
#include "sdctrl.h"
/* Definitions of physical drive number for each drive */
#define DEV_RAM 0 /* Example: Map Ramdisk to physical drive 0 */
#define DEV_MMC 1 /* Example: Map MMC/SD card to physical drive 1 */
#define DEV_USB 2 /* Example: Map USB MSD to physical drive 2 */
#define _XTAL_FREQ 8000000
/*--------------------------------------------------------------------------
Module Private Functions
---------------------------------------------------------------------------*/
/* Definitions for SDC command */
#define CMD0 (0) /* GO_IDLE_STATE */
#define CMD1 (1) /* SEND_OP_COND (MMC) */
#define ACMD41 (0x80+41) /* SEND_OP_COND (SDC) */
#define CMD8 (8) /* SEND_IF_COND */
#define CMD9 (9) /* SEND_CSD */
#define CMD10 (10) /* SEND_CID */
#define CMD12 (12) /* STOP_TRANSMISSION */
#define ACMD13 (0x80+13) /* SD_STATUS (SDC) */
#define CMD16 (16) /* SET_BLOCKLEN */
#define CMD17 (17) /* READ_SINGLE_BLOCK */
#define CMD18 (18) /* READ_MULTIPLE_BLOCK */
#define CMD23 (23) /* SET_BLOCK_COUNT (MMC) */
#define ACMD23 (0x80+23) /* SET_WR_BLK_ERASE_COUNT (SDC) */
#define CMD24 (24) /* WRITE_BLOCK */
#define CMD25 (25) /* WRITE_MULTIPLE_BLOCK */
#define CMD32 (32) /* ERASE_ER_BLK_START */
#define CMD33 (33) /* ERASE_ER_BLK_END */
#define CMD38 (38) /* ERASE */
#define CMD55 (55) /* APP_CMD */
#define CMD58 (58) /* READ_OCR */
/* MMC card type flags (MMC_GET_TYPE) */
#define CT_MMC 0x01 /* MMC ver 3 */
#define CT_SD1 0x02 /* SD ver 1 */
#define CT_SD2 0x04 /* SD ver 2 */
#define CT_SDC (CT_SD1|CT_SD2) /* SD */
#define CT_BLOCK 0x08 /* Block addressing */
static
DSTATUS Stat = STA_NOINIT; /* Disk status */
static
BYTE CardType; /* Card type flags */
/*-----------------------------------------------------------------------*/
/* Wait for card ready */
/*-----------------------------------------------------------------------*/
static
BYTE wait_ready (void) /* 1:Ready, 0:Timeout */
{
UINT tmr;
for (tmr = 5000; tmr; tmr--) { /* Wait for ready in timeout of 500ms */
if (sdspi_rxByte() == 0xFF) break;
__delay_us(100);
}
return tmr ? 1 : 0;
}
/*-----------------------------------------------------------------------*/
/* Deselect the card and release SPI bus */
/*-----------------------------------------------------------------------*/
static
void deselect (void)
{
sd_deselect(); /* Set CS# high */
sdspi_rxByte(); /* Dummy clock (force DO hi-z for multiple slave SPI) */
}
/*-----------------------------------------------------------------------*/
/* Select the card and wait for ready */
/*-----------------------------------------------------------------------*/
static
BYTE select (void) /* 1:Successful, 0:Timeout */
{
sd_select(); /* Set CS# low */
sdspi_rxByte(); /* Dummy clock (force DO enabled) */
if (wait_ready()) return 1; /* Wait for card ready */
deselect();
return 0; /* Timeout */
}
/*-----------------------------------------------------------------------*/
/* Receive a data packet from MMC */
/*-----------------------------------------------------------------------*/
static
BYTE rcvr_datablock (
BYTE *buff, /* Data buffer to store received data */
UINT btr /* Byte count (must be multiple of 4) */
)
{
BYTE token;
UINT tmr;
for (tmr = 2000; tmr; tmr--) { /* Wait for data packet in timeout of 200ms */
token = sdspi_rxByte();
if (token != 0xFF) break;
// __delay_us(100);
}
if (token != 0xFE) return 0; /* If not valid data token, retutn with error */
do
*buff++ = sdspi_rxByte(); /* Receive the data block into buffer */
while (--btr);
sdspi_rxByte(); /* Discard CRC */
sdspi_rxByte();
return 1; /* Return with success */
}
/*-----------------------------------------------------------------------*/
/* Send a data packet to MMC */
/*-----------------------------------------------------------------------*/
#if _USE_WRITE
static
BYTE xmit_datablock (
const BYTE *buff, /* 512 byte data block to be transmitted */
BYTE token /* Data/Stop token */
)
{
BYTE resp;
WORD i;
if (!wait_ready()) return 0;
sdspi_txByte(token); /* Xmit data token */
if (token != 0xFD) { /* Is data token */
i = 512;
do
{
sdspi_txByte(*buff++); /* Xmit the data block to the MMC */
__delay_us(100);
}while (--i);
sdspi_rxByte(); /* CRC (Dummy) */
sdspi_rxByte();
resp = sdspi_rxByte(); /* Reveive data response */
if ((resp & 0x1F) != 0x05) /* If not accepted, return with error */
return 0;
}
return 1;
}
#endif
/*-----------------------------------------------------------------------*/
/* Send a command packet to MMC */
/*-----------------------------------------------------------------------*/
/* NOTE: XC8 compiler is unable to allow recursion,
/ so the send_cmd function had to be divided */
#ifdef __XC8
static
BYTE __send_cmd ( /* Returns R1 resp (bit7==1:Send failed) */
BYTE cmd, /* Command index */
DWORD arg /* Argument */
)
{
BYTE n, res;
/* Select the card and wait for ready except to stop multiple block read */
if (cmd != CMD12) {
sd_deselect();
if (!select()) return 0xFF;
// sd_select();
// if (wait_ready() != 0xFF) return 0xFF;
}
/* Send command packet */
sdspi_txByte(0x40 | cmd); /* Start + Command index */
sdspi_txByte((BYTE)(arg >> 24)); /* Argument[31..24] */
sdspi_txByte((BYTE)(arg >> 16)); /* Argument[23..16] */
sdspi_txByte((BYTE)(arg >> 8)); /* Argument[15..8] */
sdspi_txByte((BYTE)arg); /* Argument[7..0] */
n = 0x01; /* Dummy CRC + Stop */
if (cmd == CMD0) n = 0x95; /* Valid CRC for CMD0(0) + Stop */
if (cmd == CMD8) n = 0x87; /* Valid CRC for CMD8(0x1AA) Stop */
sdspi_txByte(n);
/* Receive command response */
if (cmd == CMD12) sdspi_rxByte(); /* Skip a stuff byte when stop reading */
n = 10; /* Wait for a valid response in timeout of 10 attempts */
do
res = sdspi_rxByte();
while ((res & 0x80) && --n);
return res; /* Return with the response value */
}
#endif
static
BYTE send_cmd ( /* Returns R1 resp (bit7==1:Send failed) */
BYTE cmd, /* Command index */
DWORD arg /* Argument */
)
{
#ifndef __XC8
BYTE n;
#endif
BYTE res;
if (cmd & 0x80) { /* ACMD<n> is the command sequense of CMD55-CMD<n> */
cmd &= 0x7F;
#ifdef __XC8
res = __send_cmd(CMD55, 0);
#else
res = send_cmd(CMD55, 0);
#endif
if (res > 1) return res;
}
#ifdef __XC8
return __send_cmd(cmd, arg); /* Return with the response value */
#else
/* Select the card and wait for ready except to stop multiple block read */
if (cmd != CMD12) {
sd_deselect();
if (!select()) return 0xFF;
}
/* Send command packet */
sdspi_txByte(0x40 | cmd); /* Start + Command index */
sdspi_txByte((BYTE)(arg >> 24)); /* Argument[31..24] */
sdspi_txByte((BYTE)(arg >> 16)); /* Argument[23..16] */
sdspi_txByte((BYTE)(arg >> 8)); /* Argument[15..8] */
sdspi_txByte((BYTE)arg); /* Argument[7..0] */
n = 0x01; /* Dummy CRC + Stop */
if (cmd == CMD0) n = 0x95; /* Valid CRC for CMD0(0) + Stop */
if (cmd == CMD8) n = 0x87; /* Valid CRC for CMD8(0x1AA) Stop */
sdspi_txByte(n);
/* Receive command response */
if (cmd == CMD12) sdspi_rxByte(); /* Skip a stuff byte when stop reading */
n = 10; /* Wait for a valid response in timeout of 10 attempts */
do
res = sdspi_rxByte();
while ((res & 0x80) && --n);
return res; /* Return with the response value */
#endif
}
/*--------------------------------------------------------------------------
Public Functions
---------------------------------------------------------------------------*/
/*-----------------------------------------------------------------------*/
/* Initialize Disk Drive */
/*-----------------------------------------------------------------------*/
DSTATUS disk_initialize (
BYTE pdrv /* Physical drive nmuber (0) */
)
{
BYTE n, cmd, ty, ocr[4];
UINT tmr;
if (pdrv) return STA_NOINIT; /* Supports only single drive */
if (Stat & STA_NODISK) return Stat; /* No card in the socket */
sdspi_enable(); /* Enable the SPI port */
sdspi_setSlowMode(); /* Setup for slow mode */
for (n = 10; n; n--) sdspi_rxByte(); /* 80 dummy clocks */
ty = 0;
if (send_cmd(CMD0, 0) == 1) { /* Enter Idle state */
if (send_cmd(CMD8, 0x1AA) == 1) { /* SDv2? */
for (n = 0; n < 4; n++) ocr[n] = sdspi_rxByte(); /* Get trailing return value of R7 resp */
if (ocr[2] == 0x01 && ocr[3] == 0xAA) { /* The card can work at vdd range of 2.7-3.6V */
for (tmr = 1000; tmr; tmr--) { /* Wait for leaving idle state (ACMD41 with HCS bit) */
if (send_cmd(ACMD41, 1UL << 30) == 0) break;
__delay_ms(1);
}
if (tmr && send_cmd(CMD58, 0) == 0) { /* Check CCS bit in the OCR */
for (n = 0; n < 4; n++) ocr[n] = sdspi_rxByte();
ty = (ocr[0] & 0x40) ? CT_SD2 | CT_BLOCK : CT_SD2; /* SDv2 */
}
}
} else { /* SDv1 or MMCv3 */
if (send_cmd(ACMD41, 0) <= 1) {
ty = CT_SD1; cmd = ACMD41; /* SDv1 */
} else {
ty = CT_MMC; cmd = CMD1; /* MMCv3 */
}
for (tmr = 1000; tmr; tmr--) { /* Wait for leaving idle state */
if (send_cmd(cmd, 0) == 0) break;
__delay_ms(1);
}
if (!tmr || send_cmd(CMD16, 512) != 0) /* Set R/W block length to 512 */
ty = 0;
}
}
CardType = ty;
deselect();
if (ty) { /* Initialization succeded */
Stat &= ~STA_NOINIT; /* Clear STA_NOINIT */
sdspi_setFastMode();
}
return Stat;
}
/*-----------------------------------------------------------------------*/
/* Get Disk Status */
/*-----------------------------------------------------------------------*/
DSTATUS disk_status (
BYTE pdrv /* Physical drive nmuber (0) */
)
{
if (pdrv) return STA_NOINIT; /* Supports only single drive */
return Stat;
}
/*-----------------------------------------------------------------------*/
/* Read Sector(s) */
/*-----------------------------------------------------------------------*/
DRESULT disk_read (
BYTE pdrv, /* Physical drive nmuber (0) */
BYTE *buff, /* Pointer to the data buffer to store read data */
DWORD sector, /* Start sector number (LBA) */
UINT count /* Sector count (1..128) */
)
{
BYTE cmd;
if (pdrv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
if (!(CardType & CT_BLOCK)) sector *= 512; /* Convert to byte address if needed */
cmd = count > 1 ? CMD18 : CMD17; /* READ_MULTIPLE_BLOCK : READ_SINGLE_BLOCK */
if (send_cmd(cmd, sector) == 0) {
do {
if (!rcvr_datablock(buff, 512)) break;
buff += 512;
} while (--count);
if (cmd == CMD18) send_cmd(CMD12, 0); /* STOP_TRANSMISSION */
}
deselect();
return count ? RES_ERROR : RES_OK;
}
/*-----------------------------------------------------------------------*/
/* Write Sector(s) */
/*-----------------------------------------------------------------------*/
#if _USE_WRITE
DRESULT disk_write (
BYTE pdrv, /* Physical drive nmuber (0) */
const BYTE *buff, /* Pointer to the data to be written */
DWORD sector, /* Start sector number (LBA) */
UINT count /* Sector count (1..128) */
)
{
if (pdrv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
if (Stat & STA_PROTECT) return RES_WRPRT;
if (!(CardType & CT_BLOCK)) sector *= 512; /* Convert to byte address if needed */
if (count == 1) { /* Single block write */
if ((send_cmd(CMD24, sector) == 0) /* WRITE_BLOCK */
&& xmit_datablock(buff, 0xFE))
count = 0;
}
else { /* Multiple block write */
if (CardType & CT_SDC) send_cmd(ACMD23, count);
if (send_cmd(CMD25, sector) == 0) { /* WRITE_MULTIPLE_BLOCK */
do {
if (!xmit_datablock(buff, 0xFC)) break;
buff += 512;
} while (--count);
if (!xmit_datablock(0, 0xFD)) /* STOP_TRAN token */
count = 1;
}
}
deselect();
return count ? RES_ERROR : RES_OK;
}
#endif
/*-----------------------------------------------------------------------*/
/* Miscellaneous Functions */
/*-----------------------------------------------------------------------*/
//#if _USE_IOCTL
DRESULT disk_ioctl (
BYTE pdrv, /* Physical drive nmuber (0) */
BYTE cmd, /* Control code */
void *buff /* Buffer to send/receive control data */
)
{
DRESULT res;
BYTE n, csd[16], *ptr = buff;
DWORD csize;
if (pdrv) return RES_PARERR;
res = RES_ERROR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
switch (cmd) {
case CTRL_SYNC : /* Make sure that no pending write process. Do not remove this or written sector might not left updated. */
if (select()) res = RES_OK;
break;
case GET_SECTOR_COUNT : /* Get number of sectors on the disk (DWORD) */
if ((send_cmd(CMD9, 0) == 0) && rcvr_datablock(csd, 16)) {
if ((csd[0] >> 6) == 1) { /* SDC ver 2.00 */
csize = csd[9] + ((WORD)csd[8] << 8) + ((DWORD)(csd[7] & 63) << 16) + 1;
*(DWORD*)buff = csize << 10;
} else { /* SDC ver 1.XX or MMC*/
n = (csd[5] & 15) + ((csd[10] & 128) >> 7) + ((csd[9] & 3) << 1) + 2;
csize = (csd[8] >> 6) + ((WORD)csd[7] << 2) + ((WORD)(csd[6] & 3) << 10) + 1;
*(DWORD*)buff = csize << (n - 9);
}
res = RES_OK;
}
break;
case GET_BLOCK_SIZE : /* Get erase block size in unit of sector (DWORD) */
if (CardType & CT_SD2) { /* SDv2? */
if (send_cmd(ACMD13, 0) == 0) { /* Read SD status */
sdspi_rxByte();
if (rcvr_datablock(csd, 16)) { /* Read partial block */
for (n = 64 - 16; n; n--) sdspi_rxByte(); /* Purge trailing data */
*(DWORD*)buff = 16UL << (csd[10] >> 4);
res = RES_OK;
}
}
} else { /* SDv1 or MMCv3 */
if ((send_cmd(CMD9, 0) == 0) && rcvr_datablock(csd, 16)) { /* Read CSD */
if (CardType & CT_SD1) { /* SDv1 */
*(DWORD*)buff = (((csd[10] & 63) << 1) + ((WORD)(csd[11] & 128) >> 7) + 1) << ((csd[13] >> 6) - 1);
} else { /* MMCv3 */
*(DWORD*)buff = ((WORD)((csd[10] & 124) >> 2) + 1) * (((csd[11] & 3) << 3) + ((csd[11] & 224) >> 5) + 1);
}
res = RES_OK;
}
}
break;
/* Following commands are never used by FatFs module */
case MMC_GET_TYPE : /* Get card type flags (1 byte) */
*ptr = CardType;
res = RES_OK;
break;
case MMC_GET_CSD : /* Receive CSD as a data block (16 bytes) */
if (send_cmd(CMD9, 0) == 0 /* READ_CSD */
&& rcvr_datablock(ptr, 16))
res = RES_OK;
break;
case MMC_GET_CID : /* Receive CID as a data block (16 bytes) */
if (send_cmd(CMD10, 0) == 0 /* READ_CID */
&& rcvr_datablock(ptr, 16))
res = RES_OK;
break;
case MMC_GET_OCR : /* Receive OCR as an R3 resp (4 bytes) */
if (send_cmd(CMD58, 0) == 0) { /* READ_OCR */
for (n = 4; n; n--) *ptr++ = sdspi_rxByte();
res = RES_OK;
}
break;
case MMC_GET_SDSTAT : /* Receive SD statsu as a data block (64 bytes) */
if (send_cmd(ACMD13, 0) == 0) { /* SD_STATUS */
sdspi_rxByte();
if (rcvr_datablock(ptr, 64))
res = RES_OK;
}
break;
default:
res = RES_PARERR;
}
deselect();
return res;
}
//#endif
Here is the f_write() function from the ff.c
FRESULT f_write (
FIL* fp, /* Pointer to the file object */
const void* buff, /* Pointer to the data to be written */
UINT btw, /* Number of bytes to write */
UINT* bw /* Pointer to number of bytes written */
)
{
FRESULT res;
FATFS *fs;
DWORD clst, sect;
UINT wcnt, cc, csect;
const BYTE *wbuff = (const BYTE*)buff;
*bw = 0; /* Clear write byte counter */
res = validate(&fp->obj, &fs); /* Check validity of the file object */
if (res != FR_OK || (res = (FRESULT)fp->err) != FR_OK) LEAVE_FF(fs, res); /* Check validity */
if (!(fp->flag & FA_WRITE)) LEAVE_FF(fs, FR_DENIED); /* Check access mode */
/* Check fptr wrap-around (file size cannot reach 4GiB on FATxx) */
if ((!_FS_EXFAT || fs->fs_type != FS_EXFAT) && (DWORD)(fp->fptr + btw) < (DWORD)fp->fptr) {
btw = (UINT)(0xFFFFFFFF - (DWORD)fp->fptr);
}
// HERE DOES THE LOOP HAPPEN
for ( ; btw; /* Repeat until all data written */
wbuff += wcnt, fp->fptr += wcnt, fp->obj.objsize = (fp->fptr > fp->obj.objsize) ? fp->fptr : fp->obj.objsize, *bw += wcnt, btw -= wcnt) {
if (fp->fptr % SS(fs) == 0) { /* On the sector boundary? */
csect = (UINT)(fp->fptr / SS(fs)) & (fs->csize - 1); /* Sector offset in the cluster */
if (csect == 0) { /* On the cluster boundary? */
if (fp->fptr == 0) { /* On the top of the file? */
clst = fp->obj.sclust; /* Follow from the origin */
if (clst == 0) { /* If no cluster is allocated, */
clst = create_chain(&fp->obj, 0); /* create a new cluster chain */
}
} else { /* On the middle or end of the file */
#if _USE_FASTSEEK
if (fp->cltbl) {
clst = clmt_clust(fp, fp->fptr); /* Get cluster# from the CLMT */
} else
#endif
{
clst = create_chain(&fp->obj, fp->clust); /* Follow or stretch cluster chain on the FAT */
}
}
if (clst == 0) break; /* Could not allocate a new cluster (disk full) */
if (clst == 1) ABORT(fs, FR_INT_ERR);
if (clst == 0xFFFFFFFF) ABORT(fs, FR_DISK_ERR);
fp->clust = clst; /* Update current cluster */
if (fp->obj.sclust == 0) fp->obj.sclust = clst; /* Set start cluster if the first write */
}
#if _FS_TINY
if (fs->winsect == fp->sect && sync_window(fs) != FR_OK) ABORT(fs, FR_DISK_ERR); /* Write-back sector cache */
#else
if (fp->flag & FA_DIRTY) { /* Write-back sector cache */
if (disk_write(fs->drv, fp->buf, fp->sect, 1) != RES_OK) ABORT(fs, FR_DISK_ERR);
fp->flag &= (BYTE)~FA_DIRTY;
}
#endif
sect = clust2sect(fs, fp->clust); /* Get current sector */
if (!sect) ABORT(fs, FR_INT_ERR);
sect += csect;
cc = btw / SS(fs); /* When remaining bytes >= sector size, */
if (cc) { /* Write maximum contiguous sectors directly */
if (csect + cc > fs->csize) { /* Clip at cluster boundary */
cc = fs->csize - csect;
}
if (disk_write(fs->drv, wbuff, sect, cc) != RES_OK) ABORT(fs, FR_DISK_ERR);
#if _FS_MINIMIZE <= 2
#if _FS_TINY
if (fs->winsect - sect < cc) { /* Refill sector cache if it gets invalidated by the direct write */
mem_cpy(fs->win, wbuff + ((fs->winsect - sect) * SS(fs)), SS(fs));
fs->wflag = 0;
}
#else
if (fp->sect - sect < cc) { /* Refill sector cache if it gets invalidated by the direct write */
mem_cpy(fp->buf, wbuff + ((fp->sect - sect) * SS(fs)), SS(fs));
fp->flag &= (BYTE)~FA_DIRTY;
}
#endif
#endif
wcnt = SS(fs) * cc; /* Number of bytes transferred */
continue;
}
#if _FS_TINY
if (fp->fptr >= fp->obj.objsize) { /* Avoid silly cache filling on the growing edge */
if (sync_window(fs) != FR_OK) ABORT(fs, FR_DISK_ERR);
fs->winsect = sect;
}
#else
if (fp->sect != sect && /* Fill sector cache with file data */
fp->fptr < fp->obj.objsize &&
disk_read(fs->drv, fp->buf, sect, 1) != RES_OK) {
ABORT(fs, FR_DISK_ERR);
}
#endif
fp->sect = sect;
}
wcnt = SS(fs) - (UINT)fp->fptr % SS(fs); /* Number of bytes left in the sector */
if (wcnt > btw) wcnt = btw; /* Clip it by btw if needed */
#if _FS_TINY
if (move_window(fs, fp->sect) != FR_OK) ABORT(fs, FR_DISK_ERR); /* Move sector window */
mem_cpy(fs->win + fp->fptr % SS(fs), wbuff, wcnt); /* Fit data to the sector */
fs->wflag = 1;
#else
mem_cpy(fp->buf + fp->fptr % SS(fs), wbuff, wcnt); /* Fit data to the sector */
fp->flag |= FA_DIRTY;
#endif
}
fp->flag |= FA_MODIFIED; /* Set file change flag */
LEAVE_FF(fs, FR_OK);
}
Believe it or not, I had the same exact problem and messed with this for hours... It has something to do with how the XC8 compiler is interpreting the for loop iterator expressions. It looks like there's a hard limit on the number of expressions it will execute. It would be nice if the compiler at least threw a warning... to fix it, add
fp->fptr += wcnt;
fp->obj.objsize = (fp->fptr > fp->obj.objsize) ? fp->fptr : fp->obj.objsize;
*bw += wcnt;
btw -= wcnt;
to the bottom of the for loop, and change the for loop to
for ( ; btw; wbuff += wcnt){//, fp->fptr += wcnt, fp->obj.objsize = (fp->fptr > fp->obj.objsize) ? fp->fptr : fp->obj.objsize, *bw += wcnt, btw -= wcnt) {
(edit) This issue semms to be corrected in FF13 (/edit)
Same problem here. FF12c, XC8 compiler (v1.43) really seems to have a problem with the reinitialisation arguments. If you change the order and move the conditional operator ? : term to the end it works.
// wbuff += wcnt, fp->fptr += wcnt, fp->obj.objsize = (fp->fptr > fp->obj.objsize) ? fp->fptr : fp->obj.objsize, *bw += wcnt, btw -= wcnt)
wbuff += wcnt, fp->fptr += wcnt, *bw += wcnt, btw -= wcnt, fp->obj.objsize = (fp->fptr > fp->obj.objsize) ? fp->fptr : fp->obj.objsize)
The previous solution shown obove does not work for me if the first write access is for a complete sector. Because of the continue instruction the program does not execute the added code at the bottom of the loop!
-vloki-

STM32 USB OTG HOST Library hangs trying to create file with FatFs

I am trying to create a file with FatFs on USB flash, but my f_open call trying to read boot sector for first time file system mount hangs on this function.
DRESULT disk_read (
BYTE drv, /* Physical drive number (0) */
BYTE *buff, /* Pointer to the data buffer to store read data */
DWORD sector, /* Start sector number (LBA) */
BYTE count /* Sector count (1..255) */
)
{
BYTE status = USBH_MSC_OK;
if (drv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
if(HCD_IsDeviceConnected(&USB_OTG_Core))
{
do
{
status = USBH_MSC_Read10(&USB_OTG_Core, buff,sector,512 * count);
USBH_MSC_HandleBOTXfer(&USB_OTG_Core ,&USB_Host);
if(!HCD_IsDeviceConnected(&USB_OTG_Core))
{
return RES_ERROR;
}
}
while(status == USBH_MSC_BUSY ); // Loop which create hanging state
}
if(status == USBH_MSC_OK)
return RES_OK;
return RES_ERROR;
}
The main problem is the loop which creates hanging state
while(status == USBH_MSC_BUSY );
So I do not know what to do to avoid this. Using debugger I discover that state is caused by parameter CmdStateMachine of structure USBH_MSC_BOTXferParam, type USBH_BOTXfer_TypeDef is equal CMD_UNINITIALIZED_STATE which actually cause miss up of switch statement of USBH_MSC_Read10 function.
/**
* #brief USBH_MSC_Read10
* Issue the read command to the device. Once the response received,
* it updates the status to upper layer
* #param dataBuffer : DataBuffer will contain the data to be read
* #param address : Address from which the data will be read
* #param nbOfbytes : NbOfbytes to be read
* #retval Status
*/
uint8_t USBH_MSC_Read10(USB_OTG_CORE_HANDLE *pdev,
uint8_t *dataBuffer,
uint32_t address,
uint32_t nbOfbytes)
{
uint8_t index;
static USBH_MSC_Status_TypeDef status = USBH_MSC_BUSY;
uint16_t nbOfPages;
status = USBH_MSC_BUSY;
if(HCD_IsDeviceConnected(pdev))
{
switch(USBH_MSC_BOTXferParam.CmdStateMachine)
{
case CMD_SEND_STATE:
/*Prepare the CBW and relevant field*/
USBH_MSC_CBWData.field.CBWTransferLength = nbOfbytes;
USBH_MSC_CBWData.field.CBWFlags = USB_EP_DIR_IN;
USBH_MSC_CBWData.field.CBWLength = CBW_LENGTH;
USBH_MSC_BOTXferParam.pRxTxBuff = dataBuffer;
for(index = CBW_CB_LENGTH; index != 0; index--)
{
USBH_MSC_CBWData.field.CBWCB[index] = 0x00;
}
USBH_MSC_CBWData.field.CBWCB[0] = OPCODE_READ10;
/*logical block address*/
USBH_MSC_CBWData.field.CBWCB[2] = (((uint8_t*)&address)[3]);
USBH_MSC_CBWData.field.CBWCB[3] = (((uint8_t*)&address)[2]);
USBH_MSC_CBWData.field.CBWCB[4] = (((uint8_t*)&address)[1]);
USBH_MSC_CBWData.field.CBWCB[5] = (((uint8_t*)&address)[0]);
/*USBH_MSC_PAGE_LENGTH = 512*/
nbOfPages = nbOfbytes/ USBH_MSC_PAGE_LENGTH;
/*Tranfer length */
USBH_MSC_CBWData.field.CBWCB[7] = (((uint8_t *)&nbOfPages)[1]) ;
USBH_MSC_CBWData.field.CBWCB[8] = (((uint8_t *)&nbOfPages)[0]) ;
USBH_MSC_BOTXferParam.BOTState = USBH_MSC_SEND_CBW;
/* Start the transfer, then let the state machine
manage the other transactions */
USBH_MSC_BOTXferParam.MSCState = USBH_MSC_BOT_USB_TRANSFERS;
USBH_MSC_BOTXferParam.BOTXferStatus = USBH_MSC_BUSY;
USBH_MSC_BOTXferParam.CmdStateMachine = CMD_WAIT_STATUS;
status = USBH_MSC_BUSY;
break;
case CMD_WAIT_STATUS:
if((USBH_MSC_BOTXferParam.BOTXferStatus == USBH_MSC_OK) && \
(HCD_IsDeviceConnected(pdev)))
{
/* Commands successfully sent and Response Received */
USBH_MSC_BOTXferParam.CmdStateMachine = CMD_SEND_STATE;
status = USBH_MSC_OK;
}
else if (( USBH_MSC_BOTXferParam.BOTXferStatus == USBH_MSC_FAIL ) && \
(HCD_IsDeviceConnected(pdev)))
{
/* Failure Mode */
USBH_MSC_BOTXferParam.CmdStateMachine = CMD_SEND_STATE;
}
else if ( USBH_MSC_BOTXferParam.BOTXferStatus == USBH_MSC_PHASE_ERROR )
{
/* Failure Mode */
USBH_MSC_BOTXferParam.CmdStateMachine = CMD_SEND_STATE;
status = USBH_MSC_PHASE_ERROR;
}
else
{
/* Wait for the Commands to get Completed */
/* NO Change in state Machine */
}
break;
default:
break;
}
}
return status;
}
Here is USBH_BOTXfer_TypeDef type declaration;
typedef struct _BOTXfer
{
uint8_t MSCState;
uint8_t MSCStateBkp;
uint8_t MSCStateCurrent;
uint8_t CmdStateMachine;
uint8_t BOTState;
uint8_t BOTStateBkp;
uint8_t* pRxTxBuff;
uint16_t DataLength;
uint8_t BOTXferErrorCount;
uint8_t BOTXferStatus;
} USBH_BOTXfer_TypeDef;
During the debug I discover that all fields of it is 0x00.
Here are my FatFs calls
int main(void)
{
FATFS Fat;
FIL file;
FRESULT fr;
RCC->AHB1ENR |= RCC_AHB1ENR_GPIODEN;
/* Enable SWO output */
DBGMCU->CR = 0x00000020;
GPIOD->MODER=0x55000000;
GPIOD->OTYPER = 0x00000000;
GPIOD->OSPEEDR = 0x00000001;
while(1)
{
if (!USB_MSC_IsInitialized())
{
USB_MSC_Initialize();
}
if (USB_MSC_IsConnected())
{
GPIOD->ODR = (1 << 15);
disk_initialize(0);
fr = f_mount(0, &Fat);
if(fr == FR_OK)
{
fr = f_open(&file,"0:DP_lab8.pdf",(FA_CREATE_ALWAYS | FA_WRITE));
if (fr == FR_OK)
{
f_close(&file);
}
f_mount(0, NULL);
}
}
else
{
GPIOD->ODR = (1 << 14);
}
USB_MSC_Main();
}
}
USB_MSC_IsConnected function is:
int USB_MSC_IsConnected(void)
{
if (g_USB_MSC_HostStatus == USB_DEV_NOT_SUPPORTED)
{
USB_MSC_Uninitialize();
}
return !(g_USB_MSC_HostStatus == USB_DEV_DETACHED ||
g_USB_MSC_HostStatus == USB_HOST_NO_INIT ||
g_USB_MSC_HostStatus == USB_DEV_NOT_SUPPORTED);
}
And device states are:
typedef enum
{
USB_HOST_NO_INIT = 0, /* USB interface not initialized */
USB_DEV_DETACHED, /* no device connected */
USB_SPEED_ERROR, /* unsupported USB speed */
USB_DEV_NOT_SUPPORTED, /* unsupported device */
USB_DEV_WRITE_PROTECT, /* device is write protected */
USB_OVER_CURRENT, /* overcurrent detected */
USB_DEV_CONNECTED /* device connected and ready */
} USB_HostStatus;
The value of g_USB_MSC_HostStatus is received by standard USB HOST user callbacks.
I think it is a bug in ST host library. I've hunted it down, as my usb host was unable to pass enumeration stage. After a fix the stack is Ok.
There is union _USB_Setup in usbh_def.h file in "STM32Cube/Repository/STM32Cube_FW_F7_V1.13.0/Middlewares/ST/STM32_USB_Host_Library/Core/Inc" (any chip, not only F7, any version, not only V1.13.0). It has uint16_t bmRequestType and uint16_t bRequest. These two fileds must be uint8_t as of USB specs. Fixing this issue made usb host go as needed. Enumeration stage passes ok, and all other stages as well.

Changing a global variable in C

I am running a C program on an AVR chip. Whenever a serial signal is heard, it runs the serial interrupt ISR (USART_RX_vect). In this method it should turn on change to = 1;. Then in my main while loop, it should clear the LCD and display it and then set change = 0 again.
This is to stop it continually doing the calulations, and displaying the result on the LCD a million times a minute..
However, when the interrupt method changes the change variable to 1, it does not seem to change it "globally" and in the main method it is always 0..
There is a bit of stuff in here that is for debugging purposes.
/* LCD DEFINES */
#define LED PB5
#define output_low(port,pin) port &= ~(1<<pin)
#define output_high(port,pin) port |= (1<<pin)
#define set_input(portdir,pin) portdir &= ~(1<<pin)
#define set_output(portdir,pin) portdir |= (1<<pin)
/* UART SERIAL DEFINES */
#define F_CPU 16000000UL
#define BAUD 9600
#define MYUBRR F_CPU/16/BAUD-1
#define STARTCHAR 'R'
#define ENDCHAR 'E'
char reading;
char inputBuffer[12];
char readStatus;
uint8_t position;
int change;
char output;
int result;
struct Axis
{
uint8_t axisNumber;
uint16_t position;
uint16_t oldPosition;
} axis1, axis2, axis3;
/* SETUP UART */
void USART_Init( unsigned int ubrr)
{
/*Set baud rate */
UBRR0H = (unsigned char)(ubrr>>8);
UBRR0L = (unsigned char)ubrr;
/*Enable receiver and transmitter */
UCSR0B = (1<<RXEN0)|(1<<TXEN0);
/* Set frame format: 8data, 2stop bit */
UCSR0C = (1<<USBS0)|(3<<UCSZ00);
}
void USART_Transmit( unsigned char data )
{
UDR0 = data;
}
unsigned char USART_Receive( void )
{
return UDR0;
}
/*****************************************************************/
int main(void)
{
/* INITALISE SERIAL */
USART_Init(MYUBRR);
/* Turn on Receive Complete Interrupt */
UCSR0B |= (1 << RXCIE0);
/* Turn On GLobal Interrupts */
sei();
position = 0;
change = 0;
/* Initialise LCD */
lcd_init(LCD_DISP_ON); /* Initialize display, cursor off. */
lcd_clrscr();
lcd_puts("READY");
//Turn on LED 13
set_output(PORTB,LED);
output_low(PORTB,LED);
while (1) /* Loop forever */
{
if (change == 1)
{
//If not reading, display the result on the LCD display.
axis1.position = (inputBuffer[0]<< 8) | inputBuffer[1];
axis2.position = (inputBuffer[2]<< 8) | inputBuffer[3];
axis3.position = (inputBuffer[4]<< 8) | inputBuffer[5];
char axis1Printout[12];
char axis2Printout[12];
char axis3Printout[12];
sprintf(axis1Printout,"%u ", axis1.position);
sprintf(axis2Printout,"%u ", axis2.position);
sprintf(axis3Printout,"%u ", axis3.position);
char output[40] = "";
strcat(output, axis1Printout);
strcat(output, axis2Printout);
//strcat(output, axis3Printout);
lcd_clrscr(); /* Clear the screen*/
lcd_puts(output);
_delay_ms(300);
change = 0;
}
}
}
/* INTERRUPTS */
ISR (USART_RX_vect)
{
change = 1;
unsigned char input = USART_Receive();
if (input == 'R')
{
readStatus = 0; //Reading
position = 0;
}
else if ((input != 'E') && (position < 12) && (position > -1))
{
inputBuffer[position] = input;
position++;
}
else if (input == 'E')
{
readStatus = 1; //Stop Reading
position = -1;
output_high(PORTB,LED);
}
}
You need to declare change using the volatile keyword:
volatile int change;
This tells the two 'threads' (main execution loop and your ISR code) to not 'cache' the value in a register, but always retrieve it from memory.
Edit: There's another problem with the code - in your main loop, by the time you set changed to 0, you may have already had another interrupt which should have triggered your loop to run again. The easy-but-not-guaranteed fix is to immediately set changed to 0 straight after you check it. The proper way would be to use a lock - but depending on your situation, the first option might do.
Make the variable declaration volatile to ensure that a changed value is written imediately to the variable in memory.
An object shared by an interrupt handler and the application code should be qualified as volatile in the declaration.
Without the qualifier, the implementation can assume the object cannot change unexpectedly in the application code and can cache the variable (in a register for example) for optimizations while executing the application code.

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