So I can't write to internal flash memory directly after erasing it. If there's no erase operation before write operation, then I can. Any ideas as to why?
Programming function returns 'successful write' value, but when looking at memory, no data is written. Here's the code:
uint32_t pageAddress = 0x08008000;
uint16_t buffer = 0xAAAA;
HAL_FLASH_Unlock();
FLASH_PageErase(pageAddress);
HAL_FLASH_Program(TYPEPROGRAM_HALFWORD, pageAddress, buffer);
HAL_FLASH_Lock();
I've tried locking the memory between erasing and programming it, creating a delay between these operations, that doesn't help.
The problem was that PER bit in FLASH->CR register which is set when FLASH_PageErase() is called isn't cleared at the end of it. Clearing this bit while flash is still unlocked allows other operations on flash to be run after that.
STM documentation has nothing to say about this.
You can use HAL_FLASHEx_Erase instead.
uint32_t pageAddress = 0x0801FC00;
FLASH_EraseInitTypeDef EraseInitStruct;
uint32_t page_err;
EraseInitStruct.TypeErase = FLASH_TYPEERASE_PAGES;
EraseInitStruct.PageAddress = pageAddress;
EraseInitStruct.NbPages = 1;
uint32_t buffer = 0xC0FFEE;
HAL_FLASH_Unlock();
HAL_FLASHEx_Erase(&EraseInitStruct, &page_err);
HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, pageAddress, buffer);
HAL_FLASH_Lock();
Related
Can someone tell me what stupid thing I am doing wrong or understanding? As a test, I am trying to write a simple number into flash and retrieve it. Once successful, I will expand this to 6 signed values.
My device is an STM32L476RG
uint64_t data = 88;
Erase_Flash();
HAL_FLASH_Unlock();
Address = ADDR_FLASH_PAGE_256;
if (HAL_FLASH_Program(FLASH_TYPEPROGRAM_FAST, Address, data) != HAL_OK)
serprintf("Error writing flash.");
HAL_FLASH_Lock();
uint8_t *flash_biases = (uint8_t*) (ADDR_FLASH_PAGE_256);
Based on what I've read, I should be able to access the flash memory like I have. But it's not retrieving the value I expect.
The Erase_Flash() function looks like this:
void Erase_Flash() {
HAL_FLASH_Unlock();
/* Clear OPTVERR bit set on virgin samples */
__HAL_FLASH_CLEAR_FLAG(FLASH_FLAG_OPTVERR);
/* Fill EraseInit structure*/
EraseInitStruct.TypeErase = FLASH_TYPEERASE_MASSERASE;
EraseInitStruct.Banks = FLASH_BANK_2;
if (HAL_FLASHEx_Erase(&EraseInitStruct, &PAGEError) != HAL_OK) {
serprintf("Error erasing flash.");
}
HAL_FLASH_Lock();
}
FLASH_TYPEPROGRAM_FAST mode is used for writing 32 double words at once and when this mode is used, the third argument (data) becomes the raw starting address of that 32 double word data source, not the data itself.
Currently, your code fetches data from the address starting from 0x88 and writes it (a total of 256 bytes) to the flash. It appears that there is 245 on address 0x88.
You need to use FLASH_TYPEPROGRAM_DOUBLEWORD for writing uint64_t data.
There are quite a few similar questions, but none seem to have quite the same issue. I am connecting an STML4 MCU to a 6-axis sensor (LSM6DS3). I have successfully implemented everything in I2C, but would like the extra speed of SPI (and DMA, if I can get these first steps working...). So for a first step, I am trying to read the WHO_AM_I register (0x0F) of the device, which should reply with 0x69. Here is the code:
uint8_t who = 0;
// Sanity check/debugging aid should get 0x5D
who = 0x43 + 0x1A;
// Set SS low
GPIO_WritePin (GPIOB, LL_GPIO_PIN_7, GPIO_PIN_RESET);
// while tx buffer is in use, wait
while (!LL_SPI_IsActiveFlag_TXE(SPI1));
// Send READ command to the WHO_AM_I register
(SPI1->DR) = 0x8F;
// while rx buffer is in use, wait
while (!LL_SPI_IsActiveFlag_RXNE(SPI1));
// Get data off the register
who = (SPI1->DR);
// Wait for everything to wrap up before setting SS high again
while (LL_SPI_IsActiveFlag_BSY(SPI1));
// OK, now we can set SS high
GPIO_WritePin (GPIOB, LL_GPIO_PIN_7, GPIO_PIN_SET);
On the scope/analyzer, I see everything run as expected, including the sensor sending back 0x69. However, when I set a break on the other side of this code block, I see that who goes from 0 to 0x5D to 0xFF. It never reads the 0x69. I looked through other code examples and some people have a second transmit with the data set to some dummy value (usually 0xFF or 0x0), so I also tried that, but the sensor seems to get confused during the second attempt and who ends up being 0x48. I have tried every permutation of waiting for the RXNE/TXE/BSY flags that I could have, as well as many many other things to get the variable to correctly read the SPI1 data register, including reading other registers off the sensor, but all to no avail.
So then the question is, how does one correctly read values off this register?
I should also mention that I can successfully write to the device's registers. I can send the command I want, then read it back and see that it worked on the scope, even though I can never get the values assigned to a variable in code. I always get 0xFF.
I include a screen of my analyzer showing the sensor sending back 0x69 from a single read request, as well as the garbled mess it sends if I try the "dummy transmit" method.
SPI always (if the receiver is enabled) receives the data when you transfer.
This is the problem with the libraries that you do not know what is there. SPI is a lot easier to program using registers.
I assume that your data is 8bits.
You need to set the 1/4 (one byte) FIFO threshold during the SPI initialization by:
SPI1 -> CR2 |= SPI_CR2_FRXTH;
next you need to read the data from the FIFO after every write (you need also to force the compiler to use the correct size (in this case 8bits) load and store instructions):
*(volatile uint8_t *)&SPI1->DR = 0x8F; // write exactly 8 bits to the FIFO
while (!LL_SPI_IsActiveFlag_RXNE(SPI1));
dummy = *(volatile uint8_t *)&SPI-> DR;
*(volatile uint8_t *)&SPI1->DR = 0; // dummy write
while (!LL_SPI_IsActiveFlag_RXNE(SPI1));
who = *(volatile uint8_t *)&(SPI1->DR);
I do not know what is the point of using the LL libraries.
instead of
while (!LL_SPI_IsActiveFlag_RXNE(SPI1));
use registers
while (!(SPI1 -> SR & SPI_SR_RNE));
You can also wrap it into the function:
uint8_t SPI_ReadWrite8(SPI_TypeDef *spi, uint8_t data)
{
while(!(spi -> SR & SPI_SR_TXE));
*(volatile uint8_t *)&spi->DR = data;
while (!(spi -> SR & SPI_SR_RNE));
return *(volatile uint8_t *)&spi-> DR;
}
And
SPI_ReadWrite8(SPI1, 0x8f);
who = SPI_ReadWrite8(SPI1, 0);
I'm using an NXP LH79525, ARM7TDMI based processor. There is an EEPROM connected via SPI bus to the SSP port.
The objective is to read the EEPROM into SRAM for faster accessing.
The present working code sends a read command to the EEPROM, the reads the data byte per byte, which takes a long time.
I want to use the DMA to read EEPROM on the SPI bus directly, without intervention from the CPU.
Here is my code snippet:
// Initialize the DMA for use with SPI bus.
// Source is the EEPROM on the SPI bus.
// Destination is "buffer".
p_dma_stream_2->source_low = 0U;
p_dma_stream_2->source_high = 0U;
const uint32_t dest_addr = (uint32_t) buffer;
p_dma_stream_2->dest_low = (dest_addr & 0xFFFFU);
p_dma_stream_2->dest_high = (dest_addr >> 16U);
p_dma_stream_2->max_count = bytesToRead;
*p_dma_intr_mask = 0U; // Disable all dma interrupts.
*p_dma_intr_clear = 0xFF; // Clear the interrupts.
SSP->dmacr = 0x01; // Enable reading with DMA
p_dma_stream_2->control = 0x06U; // + 0x01 to enable transfer.
// 0x400 - status of stream 2. 1 == stream is active.
uint32_t status = *p_dma_status;
while ((status & 0x400U) != 0U)
{
OSTimeDelay(10U); // 10 milliseconds
status = *p_dma_status;
}
I'm reading incorrect values from the EEPROM when using the above example.
The DMA registers are counting correctly.
The SSP is already initialized before this code fragment, for reading bytes.
I'm looking for a working code example snippet, but haven't found any on the web.
According to this User's Guide table 5-1 it seems as SSPRX is assigned to Stream 0 and supports only half-word source data width (table 5-15).
Your code seems to use Stream 2 and byte adressing.
I'm trying to recreate a project of writing to an SD card (using FatFS) for a dsPIC33FJ128GP802 microcontroller.
Currently to collect the date from the SPI I have a do/while that loops 512 times and writes a dummy value to the SPI buffer, wait for the SPI flag, then read the SPI value, like so:
int c = 512;
do {
SPI1BUF = 0xFF;
while (!_SPIRBF);
*p++ = SPI1BUF;
} while (--c);
I'm trying to recreate this using the DMA intterupts but it's not working like I had hoped. I'm using one DMA channel, SPI is in 8 bit mode for the time being, so DMA is in byte mode, it's also in 'null write' mode, and continuous without ping pong. My buffers are only one member arrays and the DMA is matched.
DMA2CONbits.CHEN = 0; //Disable DMA
DMA2CONbits.SIZE = 1; //Receive bytes (8 bits)
DMA2CONbits.DIR = 0; //Receive from SPI to DMA
DMA2CONbits.HALF = 0; //Receive full blocks
DMA2CONbits.NULLW = 1; //null write mode on
DMA2CONbits.AMODE = 0; //Register indirect with post-increment
DMA2CONbits.MODE = 0; //continuous mode without ping-pong
DMA2REQbits.IRQSEL = 10; //Transfer done (SPI)
DMA2STA = __builtin_dmaoffset(SPIBuffA); //receive buffer
DMA2PAD = (volatile unsigned int) &SPI1BUF;
DMA2CNT = 0; //transfer count = 1
IFS1bits.DMA2IF = 0; //Clear DMA interrupt
IEC1bits.DMA2IE = 1; //Enable DMA interrupt
From what I understand from the null write mode, the DMA will write a null value every time a read is performed. However, the DMA wont start until an initial write is performed by the CPU, so I've used the manual/force method to start the DMA.
DMA1CONbits.CHEN = 1; //Enable DMA
DMA1REQbits.FORCE = 1; //Manual write
The interrupt will now start, and runs without error. However the code later shows that the collection was incorrect.
My interrupt is simple in that all I'm doing is placing the collected data (which I assume is placed in my DMAs buffer as allocated above) into a pointer which is used throughout my program.
void __attribute__((interrupt, no_auto_psv)) _DMA2Interrupt(void) {
if (RxDmaBuffer == 513) {
DMA2CONbits.CHEN = 0;
rxFlag = 1;
} else {
buffer[RxDmaBuffer] = SPI1BUF;
RxDmaBuffer++;
}
IFS1bits.DMA2IF = 0; // Clear the DMA0 Interrupt Flag
}
When the interrupt has run 512 times, I stop the DMA and throw a flag.
What am I missing? How is this not the same as the non-DMA method? Is it perhaps the lack of the while loop which waits for the completion of the SPI transmission (while (!_SPIRBF);). Unfortunately with the null write mode automatically sending and receiving the SPI data I can't manually put any sort of wait in.
I've also tried using two DMA channels, one to write and one to read, but this also didn't work (plus I need that channel later for when I come to proper writing to the SD card).
Any help would be great!
I want to store a number to PIC18 then retain it even if the power is lost or the unit is reset. I think my writing code portion looks fine, just the reading portion of it looks strange after the unit is reset.
I am using the following code which I got from Microchip.
Code:
unsigned int value;
unsigned int DEEdata = 1;
unsigned int DEEaddr = 0x04;
DataEEInit();
dataEEFlags.val = 0;
DataEEWrite(DEEdata,DEEaddr);
value = DataEERead(DEEaddr);
Nop();
printf("%d",value);
The ouput: 1
However when I reset the unit and only use the reading code I always get 255.
Code to read:
DataEEInit();
value = DataEERead(DEEaddr);
printf("%d",value);
The output: 255
Why is this happening? I am assuming maybe the value is not being saved or the reading portion is incorrect. Thank you!
Two functions: write to flash using 64-byte buffer # 8-byte blocks and a read/compare flash function.
For device: PIC18F46K80
Stuff for a header file:
#define PRGM_BUFFER_SIZE 8
#define TABLE_WRITE_SIZE 64
#define LOAD_TBL_PTR(x) { TBLPTRU = ((((x)>>8)>>8)&0xff);\
TBLPTRH = (((x) >> 8) & 0xff);\
TBLPTRL = ((x) & 0xff);\
}
Write to flash function:
/******************************************************
* Function : write_block
* Input : uint16_t position in destination flash
* Global : uint8_t buffer[64] - Location of source data
* Output : None
* Description : Writes the contents of the 64 byte
* data buffer to program flash space. Only 64 bytes
* can be written at once. The process of writing
* to flash is: Erase->Write.
******************************************************/
static void write_block(uint16_t addr)
{
int r, c;
// Erase flash block first. Erases a 64 byte block at a time.
LOAD_TBL_PTR(addr);
EECON1bits.EEPGD = 1; // Point to flash program memory
EECON1bits.CFGS = 0; // Access flash memory
EECON1bits.WREN = 1; // Enable write to memory
EECON1bits.FREE = 1; // Enable Erase operation
EECON2 = 0x55;
EECON2 = 0xAA;
EECON1bits.WR = 1; // Clear the flash
asm("NOP"); // Stall
// Write buffer to internal buffer. This process writes 8 bytes at a time
// so we need to loop 8 times (8*8 = 64).)
for (r = 0; r < 8; r++)
{
LOAD_TBL_PTR((addr + (r * 8)));
for (c = 0; c < PRGM_BUFFER_SIZE; c++)
{
TABLAT = buffer[(r * 8) + c];
asm("TBLWT*+"); // Push byte and then inc to next internal buffer cell
}
// Write the block to flash
asm("TBLRD*-"); // Point back to original row
// Write internal buffer to flash
EECON1bits.EEPGD = 1; // Point to flash program memory
EECON1bits.CFGS = 0; // Access flash program memory
EECON1bits.WREN = 1; // Enable write to memory
INTCONbits.GIE = 0; // Disable interrupts
EECON2 = 0x55;
EECON2 = 0xAA;
EECON1bits.WR = 1; // Start programming flash
INTCONbits.GIE = 1; // Re-enable interrupts
EECON1bits.WREN = 0; // Disable write to memory
}
}
Verify written data (demonstrates flash read)
/******************************************************
* Function : compare_block
* Input : uint16_t position in destination flash
* Global : uint8_t buffer[64] - Location of previous written data
* Output : bool true=successful, false=did not match
* Description : Reads a 64 byte block of flash memory and
* compares it to the data found in the global buffer.
******************************************************/
static bool compare_block(uint16_t addr)
{
bool retVal = true; // succeeds
uint8_t i = 0;
INTCONbits.GIE = 0; // Disable interrupts
LOAD_TBL_PTR(addr);
for (i = 0; i < TABLE_WRITE_SIZE && retVal == true; i++)
{
asm("TBLRD*+");
if (buffer[i] != TABLAT)
retVal = false;
}
INTCONbits.GIE = 1; // Enable interrupts
return retVal;
}
Yours,
Bryan Wilcutt
The device you're using doesn't have internal non-volatile memory apart from its Flash, generally used for storing code.
You have two options that I can see:
Use some external Flash or EEPROM and interface it to the External Memory Bus that's available on this PIC (see page 97 of the Family Datasheet).
Remap the internal Flash to reserve a small portion that can be used for storing your data (so that it doesn't interfere with the memory area used exclusively for code) and write your data into this region (page 87).
I haven't worked with PICs for years, so can't offer you much in the way of implementation detail but I suspect there are many examples you can source from Microchip's website.
In essence, the reason your code doesn't work is because you're trying to access memory that isn't there. If it is there, then the interface is not correct.
EDIT:
I've had a look through the code examples page for the PIC18 on Microchip's website and can't find any C examples for writing to the program memory. Unfortunately, it looks like you'll have to implement it in assembler. I don't know the semantics for the MPLAB compiler but, generally, it'll be something like this if you're going to do it inline:
void my_assembler_function(void)
{
// Inline assembler code, actioned via C.
asm("MOV x y");
asm("MOV y z");
}
Alternatively, many C compilers for microprocessor's allow you to call an external .s file with a C function call, saving you from doing it inline.
I think you can follow the example I found here to actually implement the functionality you're after.
SRAM can not be used to store Non-volatile data...
SRAM will loose data during power cycle...
Options:
1. Use internal EEPROM if available.
2. External EEPROM through I2C or SPI.
3. PIC18 Data Emulation Library.
This is an explanation of the PIC18:
/* EEPROM Read and Write Functions -- WORKING
* Used PIC18F45K22 and MPLAB and C18
* Read and Write functions work.
* EEPROM has 256 bytes of memory (256 distinct characters)
* Select "Window" -> "PIC Memory Views" -> "EE Data Memory"
* Download program to PIC18
* Hold PIC in Reset (circle arrow with pause button)
* Open EE Data Memory Tab and click "Read Device Memory" button (Top left of EE Data tab) while PIC is held in Reset
*/
This is helpful code:
#include <p18cxxx.h>
#include <p18f45k22.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#pragma config FOSC = INTIO67, PLLCFG = OFF, PRICLKEN = ON, FCMEN = ON, PWRTEN = OFF
#pragma config BOREN = SBORDIS, BORV = 250, WDTEN = OFF, WDTPS = 2048, PBADEN = OFF, WRTD = OFF
#pragma config HFOFST = OFF, MCLRE = EXTMCLR, STVREN = ON, LVP = OFF, DEBUG = ON, CPD = OFF
void EE_Write(unsigned char addr, unsigned char value);
unsigned char EE_Read(unsigned char addr);
unsigned char test;
void main(void){
OSCTUNEbits.PLLEN = 1;
OSCCON = 0x4C; //Set to use internal clock.
OSCCON2 = 0x00; // No 4x PLL
TRISB = 0x00;
ANSELB = 0x00;
PORTB = 0x00;
EE_Write(05, 0x5A);
Delay10KTCYx(50);
test = EE_Read(05);
Delay10KTCYx(50);
PORTB = 0xFF;
Delay10KTCYx(50);
PORTB = 0x00;
}
void EE_Write(unsigned char addr, unsigned char value)
{
unsigned char SaveGIE = 0;
// Set EEPROM address
EEADR = addr%256;
// Set EEPROM data
EEDATA = value;
// Select Data
EECON1bits.EEPGD = 0;
// Select EEPROM
EECON1bits.CFGS = 0;
// Enable write
EECON1bits.WREN = 1;
// Save current global interrupt enable state
SaveGIE = INTCONbits.GIE;
// Disable interrupts
INTCONbits.GIE = 0;
// Write unlock sequence
EECON2 = 0x55;
EECON2 = 0xaa;
// Start write
EECON1bits.WR = 1;
// Restore previous interrupts enable state
INTCONbits.GIE = SaveGIE;
// Wait for write completion
while(EECON1bits.WR);
// Disable writes
EECON1bits.WREN = 0;
}
unsigned char EE_Read(unsigned char addr){
while(EECON1bits.RD || EECON1bits.WR); // check the WR&RD bit to see if a RD/WR is in progress
EEADR = addr; // Write the address to EEADR.
EECON1bits.CFGS = 0;
EECON1bits.EEPGD = 0;
EECON1bits.RD = 1; // Set the RD bit to trigger the eeprom read operation.
return(EEDATA);
}
Some PIC18 micros have an internal EEPROM in addition to the internal flash. The 18F87J11 does not have this so you have 2 options:
1) Write to the flash memory - this is where your program is stored. make sure the number of write/read cycles is ok for your application.
2) Use an external i2c or spi memory for your configuration settings
The DataEEWrite you are using are from an 'eeprom emulation' library from microchip (linked in the comments below. There are a couple of things to be careful of:
Watch out when reprogramming the flash! you might overwrite your settings
Remember it isn't really eeprom! The write cycles are limited and you have to erase big sections of memory - you can't erase a single byte
The value of 255 is default value for EEPROM memory. I think after changing the code, you program microcontroller IC again. So, your EEPROM memory will be erased and return to its default value. If you use MPLAB as compiler, you can go to 'Programmer'tab > Settings.. > Program Memory > Program Options and click on Preserve EEPROM on Program.
Hope it works.
To retain the values on power cycle, SRAM memory should be used. Please confirm if you have SRAM memory available first.