Atmega32A with 16MHZ crystal oscillator runs slowly - c
I have decided to program Atmega32A in Arduino to enjoy its numerous I/O pins. To achieve that, I specified the board definition in the boards.txt file and also defined the pin mappings in the pins_arduino.h. However, the microcontroller runs slowly as if the external crystal oscillator does not take effect. The board definitions and pin mappings are shown below:
Atmega32A definition in boards.txt file:
mega32-16.name=ATmega32-External 16mhz
mega32-16.build.mcu=atmega32
mega32-16.build.f_cpu=16000000L
mega32-16.build.core=arduino:arduino
mega32-16.build.variant=mega32
mega32-16.upload.tool=avrdude
mega32-16.upload.protocol=arduino
mega32-16.upload.maximum_size=32000
mega32-16.bootloader.low_fuses=0xEF
mega32-16.bootloader.high_fuses=0x89
#mega32-16.bootloader.extended_fuses=0xFD
**pins_arduino.h **
/*
Author: Eric Conner
Email: Eric#EricConnerApps.com
Date: 06-10-2013
Project: ATmega32 for Arduino IDE
Version: v1.2
*/
#ifndef Pins_Arduino_h
#define Pins_Arduino_h
#include <avr/pgmspace.h>
#define NOT_ON_TIMER 0
#define TIMER0A 1
#define TIMER0B 2
#define TIMER1A 3
#define TIMER1B 4
#define TIMER2 5
#undef TCCR2A
#define NOT_A_PORT 0
#define NOT_ON_TIMER 0
/*
ATMEL ATmega32
+---\\---+
(XCK/T0) D0 PB0 01| |40 PA0 AI7 D31 (ADC0)
(T1) D1 PB1 02| |39 PA1 AI6 D30 (ADC1)
(INT2/AIN0) D2 PB2 03| |38 PA2 AI5 D29 (ADC2)
(OC0/AIN1) D3 PB3 04| |37 PA3 AI4 D28 (ADC3)
(SS) D4 PB4 05| |36 PA4 AI3 D27 (ADC4)
(MOSI) D5 PB5 06| |35 PA5 AI2 D26 (ADC5)
(MISO) D6 PB6 07| |34 PA6 AI1 D25 (ADC6)
(SCK) D7 PB7 08| |33 PA7 AI0 D24 (ADC7)
RESET 09| |32 AREF
VCC 10| |31 GND
GND 11| |30 AVCC
XTAL2 12| |29 PC7 D23 (TOSC2)
XTAL1 13| |28 PC6 D22 (TOSC1)
(RXD) D8 PD0 14| |27 PC5 D21 (TDI)
(TXD) D9 PD1 15| |26 PC4 D20 (TDO)
(INT0) D10 PD2 16| |25 PC3 D19 (TMS)
(INT1) D11 PD3 17| |24 PC2 D18 (TCK)
(OC1B) D12 PD4 18| |23 PC1 D17 (SDA)
(OC1A) D13 PD5 19| |22 PC0 D16 (SCL)
(ICP1) D14 PD6 20| |21 PD7 D15 (OC2)
+--------+
*/
const static uint8_t SDA = 17; //correct
const static uint8_t SCL = 16; //correct
const static uint8_t SS = 4;
const static uint8_t MOSI = 5;
const static uint8_t MISO = 6;
const static uint8_t SCK = 7;
#define NUM_DIGITAL_PINS 32
#define NUM_ANALOG_INPUTS 8
#define analogInputToDigitalPin(p) ((p < 8) ? (p) + 24 : -1)
#define digitalPinHasPWM(p) ((p) == 4 || (p) == 5 || (p) == 7)
#ifdef ARDUINO_MAIN
const uint16_t PROGMEM port_to_mode_PGM[] = {
NOT_A_PORT,
(uint16_t) &DDRA,
(uint16_t) &DDRB,
(uint16_t) &DDRC,
(uint16_t) &DDRD,
NOT_A_PORT,
NOT_A_PORT,
};
const uint16_t PROGMEM port_to_output_PGM[] = {
NOT_A_PORT,
(uint16_t) &PORTA,
(uint16_t) &PORTB,
(uint16_t) &PORTC,
(uint16_t) &PORTD,
NOT_A_PORT,
NOT_A_PORT,
};
const uint16_t PROGMEM port_to_input_PGM[] = {
NOT_A_PORT,
(uint16_t) &PINA,
(uint16_t) &PINB,
(uint16_t) &PINC,
(uint16_t) &PIND,
NOT_A_PORT,
NOT_A_PORT,
};
const uint8_t PROGMEM digital_pin_to_port_PGM[32] = {
PB, // PB0 ** D0
PB, // PB1 ** D1
PB, // PB2 ** D2
PB, // PB3 ** D3
PB, // PB4 ** D4
PB, // PB5 ** D5
PB, // PB6 ** D6
PB, // PB7 ** D7
PD, // PD0 ** D8
PD, // PD1 ** D9
PD, // PD2 ** D10
PD, // PD3 ** D11
PD, // PD4 ** D12
PD, // PD5 ** D13
PD, // PD6 ** D14
PD, // PD7 ** D15
PC, // PC0 ** D16
PC, // PC1 ** D17
PC, // PC2 ** D18
PC, // PC3 ** D19
PC, // PC4 ** D20
PC, // PC5 ** D21
PC, // PC6 ** D22
PC, // PC7 ** D23
PA, // PA7 ** A0 D24
PA, // PA6 ** A1 D25
PA, // PA5 ** A2 D26
PA, // PA4 ** A3 D27
PA, // PA3 ** A4 D28
PA, // PA2 ** A5 D29
PA, // PA1 ** A6 D30
PA, // PA0 ** A7 D31
};
const uint8_t PROGMEM digital_pin_to_bit_mask_PGM[32] = {
_BV(0), // PB0 ** D0
_BV(1), // PB1 ** D1
_BV(2), // PB2 ** D2
_BV(3), // PB3 ** D3
_BV(4), // PB4 ** D4
_BV(5), // PB5 ** D5
_BV(6), // PB6 ** D6
_BV(7), // PB7 ** D7
_BV(0), // PD0 ** D8
_BV(1), // PD1 ** D9
_BV(2), // PD2 ** D10
_BV(3), // PD3 ** D11
_BV(4), // PD4 ** D12
_BV(5), // PD5 ** D13
_BV(6), // PD6 ** D14
_BV(7), // PD7 ** D15
_BV(0), // PC0 ** D16
_BV(1), // PC1 ** D17
_BV(2), // PC2 ** D18
_BV(3), // PC3 ** D19
_BV(4), // PC4 ** D20
_BV(5), // PC5 ** D21
_BV(6), // PC6 ** D22
_BV(7), // PC7 ** D23
_BV(7), // PA7 ** A0 D24
_BV(6), // PA6 ** A1 D25
_BV(5), // PA5 ** A2 D26
_BV(4), // PA4 ** A3 D27
_BV(3), // PA3 ** A4 D28
_BV(2), // PA2 ** A5 D29
_BV(1), // PA1 ** A6 D30
_BV(0), // PA0 ** A7 D31
};
const uint8_t PROGMEM digital_pin_to_timer_PGM[32] = {
NOT_ON_TIMER, // PB0 ** D0
NOT_ON_TIMER, // PB1 ** D1
NOT_ON_TIMER, // PB2 ** D2
TIMER0A, // PB3 ** D3
NOT_ON_TIMER, // PB4 ** D4
NOT_ON_TIMER, // PB5 ** D5
NOT_ON_TIMER, // PB6 ** D6
NOT_ON_TIMER, // PB7 ** D7
NOT_ON_TIMER, // PD0 ** D8
NOT_ON_TIMER, // PD1 ** D9
NOT_ON_TIMER, // PD2 ** D10
NOT_ON_TIMER, // PD3 ** D11
TIMER1B, // PD4 ** D12
TIMER1A, // PD5 ** D13
NOT_ON_TIMER, // PD6 ** D14
TIMER2, // PD7 ** D15
NOT_ON_TIMER, // PC0 ** D16
NOT_ON_TIMER, // PC1 ** D17
NOT_ON_TIMER, // PC2 ** D18
NOT_ON_TIMER, // PC3 ** D19
NOT_ON_TIMER, // PC4 ** D20
NOT_ON_TIMER, // PC5 ** D21
NOT_ON_TIMER, // PC6 ** D22
NOT_ON_TIMER, // PC7 ** D23
NOT_ON_TIMER, // PA7 ** A0 D24
NOT_ON_TIMER, // PA6 ** A1 D25
NOT_ON_TIMER, // PA5 ** A2 D26
NOT_ON_TIMER, // PA4 ** A3 D27
NOT_ON_TIMER, // PA3 ** A4 D28
NOT_ON_TIMER, // PA2 ** A5 D29
NOT_ON_TIMER, // PA1 ** A6 D30
NOT_ON_TIMER, // PA0 ** A7 D31
};
#endif
#endif
My problem here is, calling delay(100) function causes delay of more than 1000 milli seconds instead of 100 milli seconds. What do I do to get correct clock frequency according to 16MHZ oscillator?
I tried to change the crystall oscillator but nothing changes.
AFAIK, there's only few things that might impact incorrect delay:
F_CPU, which is present in your config and I believe already passed to your compiler - I would check this.
Clock fuse settings - check CKDIV8, etc.
Clock related registers - check CLKPR, CLKPCE, etc. Note, this step might be not required if fuses are programmed for a correct speed.
Wrong value of an oscillator.
Thanks a lot to everyone who helped me in one way or the other. I was able to get the microcontroller working with 16MHZ external oscillator by taking the following steps:
Installed AVRDUDE
Connected USBtinyISP to the microcontroller through ISP interface.
Run the following command in the command prompt to set low and high fuses of the microcontroller: avrdude -c usbtiny -p m32 -U lfuse:w:0xbf:m -U hfuse:w:0xce:m
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I'm running some tests on STM32L152 by trying to control a DC motor speed by selecting 3 different speeds using a push button, as following: ideal mode, motor is off. push button pressed, motor runs at speed-1 push button pressed again, motor runs at speed-2 push button pressed again, motor stops. I've already tried to run the motor directly by setting CCR1 (TIM4), and it works perfectly. so I believe the only issue is with the push button part. here's the code: #include <stdio.h> #include "stm32l1xx.h" // Keil::Device:Startup // initialization of GPIOB, GPIOA & PWM/TIM4 void GPIO_Init() { // initialization of GPIOB RCC->AHBRSTR |= RCC_AHBRSTR_GPIOBRST; /* Reset GPIOB clock */ RCC->AHBENR |= RCC_AHBENR_GPIOBEN; /* Enable GPIOB clock*/ GPIOB->MODER &= ~(0x03 << (2 * 6)); /* Clear bit 12 & 13 Output mode*/ GPIOB->MODER |= 0x01 << (2 * 6); /* set as Output mode*/ GPIOB->OSPEEDR &= ~(0x03 << (2 * 6)); /* 40 MHz speed */ GPIOB->OSPEEDR |= 0x03 << (2 * 6); /* 40 MHz speed*/ GPIOB->PUPDR &= ~(1 << 6); /* NO PULL-UP PULL-DOWN*/ GPIOB->OTYPER &= ~(1 << 6); /* PUSH-PULL*/ GPIOB->AFR[0] |= 0x2 << (4 * 6); // initialization of GPIOA RCC->AHBRSTR |= RCC_AHBRSTR_GPIOARST; /* Reset GPIOA clock*/ RCC->AHBENR |= RCC_AHBENR_GPIOAEN; /* Enable GPIOA clock*/ GPIOA->MODER &= ~(0x03); /* Clear & set as input*/ GPIOA->OSPEEDR &= ~(0x03); /* 2 MHz speed */ GPIOA->OSPEEDR |= 0x01; /* 2 MHz speed */ GPIOA->PUPDR &= ~(0x03); /* No PULL-UP/DOWN */ GPIOA->OTYPER &= ~(0x1); /* PUSH-PULL */ //initialization of PWM & TIM4 RCC->APB1ENR |= RCC_APB1ENR_TIM4EN; TIM4->PSC = 100; TIM4->ARR = 414; // F=2.097MHz , Fck= 2097000/(100+1)= 20.762KHz, Tpwm = 0.02, ARR= (Fck x Tpwm)-1 TIM4->CCMR1 |= TIM_CCMR1_OC1M_1 | TIM_CCMR1_OC1M_2; // 111: PWM mode 1 TIM4->CCMR1 |= TIM_CCMR1_OC1PE; TIM4->CR1 |= TIM_CR1_ARPE; TIM4->CCER |= TIM_CCER_CC1E; TIM4->EGR |= TIM_EGR_UG; TIM4->SR &= ~TIM_SR_UIF; TIM4->DIER |= TIM_DIER_UIE; TIM4->CR1 |= TIM_CR1_CEN; } // Delay conf void setSysTick(void) { // ---------- SysTick timer (1ms) -------- // if (SysTick_Config(SystemCoreClock / 1000)) { // Capture error while (1) { }; } } volatile uint32_t msTicks; //counts 1ms timeTicks void SysTick_Handler(void) { msTicks++; } static void Delay(__IO uint32_t dlyTicks) { uint32_t curTicks = msTicks; while ((msTicks - curTicks) < dlyTicks); } int returnVal = 0; int updatedpress = 0; int buttonpress() // function to check & add, if the pushbutton is pressed { if (GPIOA->IDR & GPIO_IDR_IDR_0) //condition: if PA0 is set { Delay(500); // avoid debouncing if (GPIOA->IDR & GPIO_IDR_IDR_0) //confirm condition: if PA0 is set { returnVal = 1 + updatedpress; while (GPIOA->IDR & GPIO_IDR_IDR_0) { } } } return returnVal; } int main(void) { GPIO_Init(); setSysTick(); while (1) { int buttonpress(); updatedpress = returnVal; if (updatedpress == 1) TIM4->CCR1 = 30; else if (updatedpress == 2) TIM4->CCR1 = 37; else if (updatedpress == 3) TIM4->CCR1 = 46; else if (updatedpress > 3) returnVal = 0; } } When I run the code, nothing works physiclly. I tried to run the debugger and I found that it exits the buttonpress function immedtialy after reaching if(GPIOA->IDR & GPIO_IDR_IDR_0) Any idea why it doesn't work as it should?
The GPIO peripherals are held in reset, you should clear the reset bits: RCC->AHBRSTR |= RCC_AHBRSTR_GPIOBRST RCC->AHBRSTR &= ~RCC_AHBRSTR_GPIOBRST /* ... */ RCC->AHBRSTR |= RCC_AHBRSTR_GPIOARST; RCC->AHBRSTR &= ~RCC_AHBRSTR_GPIOARST;
Ok it worked, and here are the corrections made: 1/ PB6 (which is connected to the DC motor) was mistakenly set as output. changed to Alternate Function. 2/ If-Conditions used for comparing the number of button-press and select motor speed is shifted to a separate function called runmotor 3/ The read instruction if(GPIOA->IDR & 0x0001) is moved into the while loop within the main function to ensure a continuous check of the pushbutton condition. 4/ Reset of GPIOs are cleared, as advised by #berendi here's the updated code: #include <stdio.h> #include "stm32l1xx.h" // Keil::Device:Startup // initialization of GPIOB, GPIOA & PWM/TIM4 void GPIO_Init(){ // initialization of GPIOB RCC->AHBRSTR |= RCC_AHBRSTR_GPIOBRST; /* Reset GPIOB clock*/ RCC->AHBRSTR &= ~RCC_AHBRSTR_GPIOBRST; /* Clear Reset */ RCC->AHBENR |= RCC_AHBENR_GPIOBEN; /* Enable GPIOB clock*/ GPIOB->MODER &= ~(0x03 << (2*6)); /* Clear bit 12 & 13 */ GPIOB->MODER |= 0x02 << (2*6); /* set as Alternate function*/ GPIOB->OSPEEDR &= ~(0x03<< (2*6)); /* 40 MHz speed*/ GPIOB->OSPEEDR |= 0x03<< (2*6); /* 40 MHz speed */ GPIOB->PUPDR &= ~(1<<6); /* NO PULL-UP PULL-DOWN*/ GPIOB->OTYPER &= ~(1<<6); /* PUSH-PULL*/ GPIOB->AFR[0] |= 0x2 << (4*6); // initialization of GPIOA RCC->AHBRSTR |= RCC_AHBRSTR_GPIOARST; /* Reset GPIOA clock */ RCC->AHBRSTR &= ~RCC_AHBRSTR_GPIOARST; /* Clear Reset */ RCC->AHBENR |= RCC_AHBENR_GPIOAEN; /* Enable GPIOA clock */ GPIOA->MODER &= ~(0x03); /* Clear & set as input */ GPIOA->OSPEEDR &= ~(0x03); /* 2 MHz speed */ GPIOA->OSPEEDR |= 0x01; /* 2 MHz speed */ GPIOA->PUPDR &= ~(0x03); /* reset PULL-DOWN */ GPIOA->OTYPER &= ~(0x1); /* PUSH-PULL */ //initialization of PWM & TIM4 RCC->APB1ENR |= RCC_APB1ENR_TIM4EN; TIM4->PSC = 100; TIM4->ARR = 414; // F=2.097MHz , Fck= 2097000/(100+1)= 20.762KHz, Tpwm = 0.02, ARR= (Fck x Tpwm)-1 TIM4->CCMR1 |= TIM_CCMR1_OC1M_1 | TIM_CCMR1_OC1M_2; // 111: PWM mode 1 TIM4->CCMR1 |= TIM_CCMR1_OC1PE; TIM4->CR1 |= TIM_CR1_ARPE; TIM4->CCER |= TIM_CCER_CC1E; TIM4->EGR |= TIM_EGR_UG; TIM4->SR &= ~TIM_SR_UIF; TIM4->DIER |= TIM_DIER_UIE; TIM4->CR1 |= TIM_CR1_CEN; } void setSysTick(void){ // ---------- SysTick timer (1ms) -------- // if (SysTick_Config(SystemCoreClock / 1000)) { // Capture error while (1){}; } } volatile uint32_t msTicks; //counts 1ms timeTicks void SysTick_Handler(void) { msTicks++; } static void Delay(__IO uint32_t dlyTicks){ uint32_t curTicks = msTicks; while ((msTicks - curTicks) < dlyTicks); } int buttonpress=0; static void runmotor(void) { if (buttonpress ==1){ TIM4->CCR1 = 30; return; } if (buttonpress ==2){ TIM4->CCR1 = 37; return; } if (buttonpress ==3){ TIM4->CCR1 = 46; return; } if (buttonpress > 3){ TIM4->CCR1 = 0; buttonpress = 0; return; } } int main(void){ GPIO_Init(); setSysTick(); while (1){ if(GPIOA->IDR & 0x0001) { Delay(5); if(GPIOA->IDR & 0x0001) buttonpress = buttonpress + 1; runmotor(); } } }