I cant seem to get my head round configuring the internal clock as an output.
I'm looking to output a 32MHz clock on PA22 or Digital Pin 1 on the adafruit metro M4 Express.
here is my code
void setup()
{
GCLK->GENCTRL[7].reg = GCLK_GENCTRL_OE | // Enable the GCLK output
GCLK_GENCTRL_IDC | // Set the duty cycle to 50/50 HIGH/LOW
GCLK_GENCTRL_GENEN |
GCLK_GENCTRL_SRC_DFLL;
while(GCLK->SYNCBUSY.bit.GENCTRL7);
PORT->Group[g_APinDescription[1].ulPort].PINCFG[g_APinDescription[1].ulPin].bit.PMUXEN = 1;
PORT->Group[g_APinDescription[1].ulPort].PMUX[g_APinDescription[1].ulPin >> 1].reg |= PORT_PMUX_PMUXO(1);
}
any help much appreciated
Related
I am developing a simple program to run a buzzer in AVR on a Teensy 2.0 (ATMEGA32u4) and I am having great difficulty getting the PWM output to work. The PWM output is on PB6 and I can test it digitally so I am not worried about the hardware setup of the buzzer.
Eventually, the PWM will have a 50% duty cycle and the frequency will modulate, however, I am more concerned I am not getting any output at this point.
I have tried several different PWM setups and even have a second timer running to complete other tasks.
Here is my setup and program skeleton:
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
void button_handler(void);
void setup(void)
{
cli(); // Disable interrupts
// Set sysclk to 16 MHz
CLKPR = (1<<CLKPCE); // Prescaler change enable
CLKPR = 0x00; // Set prescaler to zero
DDRB = (1<<DDB6); // configure PORT B6 (buzzer) as output
// initliase timer1
// Fast PWM, TOP = OCR1A, Update OCR1B at TOP, TOV1 flag set on TOP
// Clear OC1B on compare match, set OC1B at TOP
// clkI/O/1 (No prescaling)
TCCR1A = (1<<COM1B1)|(1<<WGM11)|(1<<WGM10);
TCCR1B = (1<<WGM13)|(1<<WGM12)|(1<<CS10);
OCR1A = 1023; // Setup PWM Registers
OCR1B = 511; // 50% duty cycle
sei(); // Enable interrupts
}
int main(void)
{
setup(); // initialise device
for (;;)
{
// runs led blinking on PORTD, removed for simplicity
}
}
Really struggling to see where I am going wrong so any help would be much appreciated!
Finally managed a fix coming back after a few months, a simple clean fixed the issue.
I am currently working on a low-power project using the Adafruit Feather M0 microprocessor. A requirement of my project is to be able to sleep the CPU and wake it again using an external interrupt triggered from the MPU6050 accelerometer.
I have tested the following code sample from GitHub - it works successfully! The question that I need answering is how to I alter this sample code to work on Pin 13 of the feather, rather than pin 6.
#define interruptPin 6
volatile bool SLEEP_FLAG;
void EIC_ISR(void) {
SLEEP_FLAG ^= true; // toggle SLEEP_FLAG by XORing it against true
//Serial.print("EIC_ISR SLEEP_FLAG = ");
//Serial.println(SLEEP_FLAG);
}
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
delay(3000); // wait for console opening
attachInterrupt(digitalPinToInterrupt(interruptPin), EIC_ISR, CHANGE); // Attach interrupt to pin 6 with an ISR and when the pin state CHANGEs
SYSCTRL->XOSC32K.reg |= (SYSCTRL_XOSC32K_RUNSTDBY | SYSCTRL_XOSC32K_ONDEMAND); // set external 32k oscillator to run when idle or sleep mode is chosen
REG_GCLK_CLKCTRL |= GCLK_CLKCTRL_ID(GCM_EIC) | // generic clock multiplexer id for the external interrupt controller
GCLK_CLKCTRL_GEN_GCLK1 | // generic clock 1 which is xosc32k
GCLK_CLKCTRL_CLKEN; // enable it
while (GCLK->STATUS.bit.SYNCBUSY); // write protected, wait for sync
EIC->WAKEUP.reg |= EIC_WAKEUP_WAKEUPEN4; // Set External Interrupt Controller to use channel 4 (pin 6)
PM->SLEEP.reg |= PM_SLEEP_IDLE_CPU; // Enable Idle0 mode - sleep CPU clock only
//PM->SLEEP.reg |= PM_SLEEP_IDLE_AHB; // Idle1 - sleep CPU and AHB clocks
//PM->SLEEP.reg |= PM_SLEEP_IDLE_APB; // Idle2 - sleep CPU, AHB, and APB clocks
// It is either Idle mode or Standby mode, not both.
SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk; // Enable Standby or "deep sleep" mode
SLEEP_FLAG = false; // begin awake
// Built-in LED set to output and high
PORT->Group[g_APinDescription[LED_BUILTIN].ulPort].DIRSET.reg = (uint32_t)(1<<g_APinDescription[LED_BUILTIN].ulPin); // set pin direction to output
PORT->Group[g_APinDescription[LED_BUILTIN].ulPort].OUTSET.reg = (uint32_t)(1<<g_APinDescription[LED_BUILTIN].ulPin); // set pin mode to high
Serial.println("Setup() Run!");
}
void loop() {
// put your main code here, to run repeatedly:
if (SLEEP_FLAG == true) {
PORT->Group[g_APinDescription[LED_BUILTIN].ulPort].OUTCLR.reg = (uint32_t)(1<<g_APinDescription[LED_BUILTIN].ulPin); // set pin mode to low
Serial.println("I'm going to sleep now.");
__WFI(); // wake from interrupt
SLEEP_FLAG = false;
Serial.println("Ok, I'm awake");
Serial.println();
}
//Serial.print("SLEEP_FLAG = ");
//Serial.println(SLEEP_FLAG);
PORT->Group[g_APinDescription[LED_BUILTIN].ulPort].OUTTGL.reg = (uint32_t)(1<<g_APinDescription[LED_BUILTIN].ulPin); // toggle output of built-in LED pin
delay(1000);
}
As per the pinout diagram and Atmel datasheet, I am struggling to work out which changes to make to allow pin 13 to operate in the same way as pin 6.
Atmel Datasheet
The obvious solution is to change the following lines...
#define interruptPin 13
EIC->WAKEUP.reg |= EIC_WAKEUP_WAKEUPEN1; // Set External Interrupt Controller to use channel 4 (pin 6)
I suspected channel 1 (WAKEUPEN1) due to the ENINT^1 next to pin 13 on the pinout diagram. But this didn't work, the code pin operation did not exhibit the same behaviour as the pin 6 setup.
I would be very grateful for any suggestion of how to implement this code working on Pin 13. Many thanks for your support.
I'm not an authority here, and your code looks correct to me.
Except, the pin out shows Pin 13 is the built-in LED line, and you manipulate LED_BUILTIN several places in your code. That's almost certainly conflicting with your attempts to use 13 as an interrupt line.
I am a beginner coder learning on the MSP430FR4133.
I'm using a servo motor as part of my system, which is controlled by PWM.
The motor rotates across 180°, with a 1ms pulse being far right and 2ms pulse being far left in a 20ms period. Unfortunately I'm simply having no success operating it.
I have some very simple code that my intention was to simply force the motor to the right-most position:
WDTCTL = WDTPW | WDTHOLD;
P1DIR |= BIT7; //P1.7 Output
P1SEL0 |= BIT7; //P1.7 Select
TA0CCR0 = 20000-1; //Set Period to 20ms.
TA0CCTL1 = OUTMOD_7; //CCR1 Reset/Set
TA0CCR1 = 1000; //Set Duty Cycle to 1ms
TA0CTL = TASSEL_SMCLK | MC_UP | TACLR; //Use SMCLK in Up Mode
Unfortunately, the code isn't operating as I intended. The motor is supplied by a 5v supply, though the PWM signal from the MPS430 is only 3.3v. Could this also be an issue?
Thanks for any assisstance, and I can expand on anything I have not given enough information on.
I'm new to microcontrollers, so I'm interested is it possible to set correct frequency mode on TCCR2 8bit timer?I need it to control a servo;
On TCCR1 I do smth like this:
DDRB |= (1<<1) | (1<<2);
ICR1 = 20000;
TCCR1A = (1<<WGM11)|(1<<COM1A1) | (1<<COM1B1);
TCCR1B = (1<<WGM13) | (1<<WGM12) | (1<<CS10);
OCR1A = 1500;//middle pos
And it works fine, but it seems there is no "ICR2" register and no capture mode on this timer, so I don't understand how can I set frequency to control servo on PB3.Is there any onter ways to control servos?
Thanks!
Input Capture does not set a pin, so it can't be used to control a servo. ICR1 is usually used for input compare, but is also used for output compare on Timer 1 in some PWM modes.
PB3 is controlled by the output compare on Timer 2. You have do set it up similarly to what you have for Timer 1. The OCR2 register may be relevant to your needs.
I am having trouble setting up high speed PWM on my ATtiny85. I need to use the PCK, at a speed of 400 kHz. I believe that I have followed the data sheet correctly, but for some reason, the timer interrupt flags are not working.
If I program the device, the output of the corresponding pin is a constant 5 V.
If I comment out the PCK setup and use the system clock instead, the flags are correctly set and PWM works fine. The code is posted. Why aren't the flags setting and the PWM isn't working?
#include <avr/io.h>
#include <avr/interrupt.h>
int main(void)
{
PORTB = 0; //Reset values on port B
// After setting up the timer counter,
// set the direction of the ports to output
DDRB |= (1<<PB1) | (1<<PB0); // Set the direction of PB1 to an output
// PLLCSR - PLL control and status register:
// PLL is a clock multiplier - multiplies system 8 MHz by 8 to 64 MHz
// PLL is enabled when:PLLE bit is enabled,
// CKSEL fuse is programmed to 0001. This clock is
// switched off in sleep modes!
PLLCSR |= (1<<PLLE); // PLL enable
// Wait until the PLOCK bit is enabled
// before allowing the PCK to be enabled
//WaitForPLOCK();
//unsigned int i = 0;
while ((PLLCSR & (1<<PLOCK)) == 0x00)
{
// Do nothing until plock bit is set
}
PLLCSR |= (1<<PCKE); // Enable asynchronous mode, sets PWM clock source
TCCR1 =
(1<<CTC1) | // Enable PWM
(1<<PWM1A) | // Set source to pck
(1<<(CS10)) | // Clear the pin when match with ocr1x
(1<<COM1A1);
GTCCR = (1<<PWM1B) | (1<<COM1B1);
// Set PWM TOP value - counter will count and reset
// after reaching this value
// OCR1C
// 400 kHz 159
// 450 kHz 141
// 500 kHz 127
OCR1C = 159;
// Enable Timer1 OVF interrupt
TIMSK = (1<<OCIE1A) | (1<<TOIE1);
sei();
// This should set the duty cycle to about 75%
OCR1A = 120;
The solution involved the CKDIV8 fuse. To program this fuse correctly however, HVSP "High Voltage Serial Programming" was required. After removing this fuse so that the device operated at 8 MHz, the PWM gave a 400 kHz output. I hope other people find this useful!
The errata (section 27 of the datasheet) states 'PLL will not lock under 6 MHz'. The only workaround listed is to set the clock to 6 MHz or higher.