All Questions
Tagged with interrupts avr
125 questions
2
votes
1
answer
15k
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Use AVR Timer1 for Compare Interrupt AND PWM at same time
Is it possible to use Timer1 on an ATMega to generate a compare interrupt on OCR1A and PWM output on OCR1B? I've tried with similar to the following, but neither work with everything I've tried.
<...
- 1,623
2
votes
1
answer
958
views
AVR Interrupt "Interference"
I'm currently working on receiving signals from an RC remote. I have used pins A8 to A15 on my Arduino Mega board.
The ports and interrupts are setup with the help of this code:
...
- 23
2
votes
1
answer
1k
views
Atmega328P Watch Dog Timer - Delay Issue
I am trying to give delay of 0.5 seconds on 13 pin of the arduino using Watch Dog timer interrupt, the code complies and works fine but the led is blinking so rapidly that it seems like it is ...
- 37
2
votes
1
answer
1k
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Valid use of ISR_NOBLOCK
I am using two timer interrupts:
TIMER0_OVF triggered every 12 ms, with its ISR only polling a pin, conditionally setting a flag and incrementing a value, so it ...
- 551
2
votes
1
answer
1k
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Attiny10 not triggering timer overflow interrupt while simulation (Atmel Studio 6)
I have problems simulating the timer overflow in Atmel Studio 6. The code is for an Attiny10 and looks like below. As far as I know I set all the neccessary bits to enable the counter (which works in ...
- 123
2
votes
1
answer
2k
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How to implement a synchronization signal with AVR (attiny45)?
In pseudocode I want to do following:
...
- 188
2
votes
3
answers
486
views
How to reduce the effect of electric lighter noise on Micro controller?
I am using a kind of electric lighter in my circuit in order to turn the fire on.
And also i have used some sensors that alert in danger by sending a signal to the MCU (ATmega 32) interrupt.
The ...
2
votes
2
answers
752
views
Unexplained interrupt behavior in AVR ATMEGA324P Timer Counter ISR
I have an ATMEGA324P controlling a dual motor driver circuit. I'm using the 16-bit Timer Counter 1 in Phase and Frequency Correct mode to create (2) PWM outputs using the ICR1 as the TOP value and the ...
- 365
2
votes
0
answers
993
views
AVR interrupt setup seems to stop program execution
On ATMEGA168PA I have problems with interrupt-driven character reception over UART. When I include the line setup_interrupt() it seems that program execution stops ...
2
votes
1
answer
620
views
Pullup Rise Time On AVR External Interrupt
Background
I am designing a simple lamp dimmer using the Atmel ATTiny441 microcontroller. To this end, I have designed a very basic zero-cross detector which feeds the external interrupt pin (INT0) ...
- 167
1
vote
2
answers
287
views
Does this interrupt improve performance even with while loop in ISR?
Note: I am a beginner :) MCU: Atmega328p
Which program below burdens the CPU the least? Would it be a significant difference?
Objective: to make a more "efficient" serial monitor by ...
- 479
1
vote
2
answers
305
views
Where should be defined a device specific ISR when making a static library?
Suppose I want to make a static library (.a file), which contains an ISR. That library should be used by many AVR MCUs, but each device has different ISR vector name, so it cannot be defined in .c ...
- 13
1
vote
2
answers
3k
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Blinking led using interrupts in AVR
I want to learn how to work with interrupts and I have done my first try.
I have done a very simple circuit based on ATtiny13.
There's a led in PB1 and a button in PB3. When the button is pressed, ...
- 59
1
vote
2
answers
856
views
Unable to set Pin Change Interrupt on ATmega328p
so I am working on learning some AVR programming with the ATmega328p. I am trying to set up a pin change interrupt and this is the code I am running. However, the interrupt never seems to trigger. ...
- 143
1
vote
2
answers
543
views
USART ISR keeps repeating 4 times
Hi,
I'm having a problem with the USART_RX_vect interrupt of the ATMega 328p. The receiving works fine and I'm able to evaluate the sent bits (so it's not due to the baudrate) but everytime I send a ...
- 11
1
vote
3
answers
1k
views
ATmega1284P int0 interrupt sw0
I want to toggle the LED3 of the microcontroller when the button SW0 is pressed. I developed this code but it is not working and I dont know what is wrong. I search in the documentation and many foros ...
- 21
1
vote
1
answer
637
views
AVR ATmega: can I trigger external interrupt by setting corresponding INTF flag bit?
I'm writing a C program for ATmega64A which has a INT0 ISR. This ISR should be executed in case of INT0 falling edge OR if the TIMER3 goes overflow.
To avoid doubling the code I'd like to trigger ...
- 3,032
1
vote
1
answer
1k
views
AVR: Interrupt build error
I am trying to learn how to use interrupts for a project using an Attiny85. I have written a simple program from what I have learned from tutorials. However when I try to build the program in Atmel ...
1
vote
1
answer
255
views
AVR- state change of a pin to generate an interrupt [closed]
I need to produce external interrupt whenever there is a change in state of a pin. When the pin goes from high impedance state to ground or from ground to high impedance state, an interrupt must be ...
- 403
1
vote
1
answer
75
views
Cannot stop Microcontroller's Hardware Timer from running
I'm using an Atmel ATMega8 microcontroller to control a stepper motor. (Datasheet).
Timer1 (a 16-bit hardware counter) is used in CTC mode to modulate an IO pin to provide the stepping signal to the ...
- 656
1
vote
1
answer
1k
views
AVR pin change interrupt
I want to turn on LEDs 0, 1 and 2 when pinc1, pinc2 and pinc3 are triggered. Also, I want to use a pin change interrupt.
Problem: only LED 1 is on.
This is my code and I am using atmega328p and ...
- 355
1
vote
1
answer
3k
views
AVR bootloader interrupt issue
For a quite while, I've been using an avr ATmega324PA controller and Atmel studio to write the programs. we wrote a TCP bootloader. It works fine without any interrupt. Later we did add an external ...
- 403
1
vote
1
answer
604
views
Where is Interrupt Vector Table stored in ATmega32A?
Given that Atmega32A has three types of memory :
1) SRAM.
2) Flash (Program memory).
3)EEPROM.
In which section the Interrupt Vector Table is stored ?
- 105
1
vote
1
answer
1k
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Timer1 on ATtiny85 not working as expected
I am trying to use Timer1 on the ATtiny85 (Adafruit Trinket) to blink an LED every second. The prescaler value is 1024, and the compare register value is 28. I loop through this 279 times to get a ...
- 1,409
1
vote
1
answer
643
views
Interrupts in AVR
I'm using an atmega328 on AVR. I haven't done any coding yet but I am planning. How I will do so in my head. So I want to be able to wake up the ATmega328 via a button press, and go to sleep after I'...
1
vote
1
answer
695
views
Can't get AVR pin change interrupt to work
I'm trying to get a pin change interrupt on an Attiny2313 to work but i'm stuck,
the interrupt is not triggering.
I'm using the following code in main():
...
- 209
1
vote
2
answers
3k
views
Determine input frequency of square wave w/ ICR in Atmega328p
I'm trying to obtain the input frequency of a square wave using the input capture register of an Atmega328p. So far, it works sporadically -- which is to say, when I input a 75 kHz square wave, the ...
- 35
1
vote
1
answer
10k
views
Stop timer set new value and start again AVR (Interrupt)
I have AVR MCU.
I am playing with timer now.
What I need ? I have timer counting up with some frequency. In each interrupt I am incrementing variable, and somewhere I need to check value of this ...
1
vote
1
answer
1k
views
How to detect which timer interrupt called callback when using ASF?
I have a general function, which gets passed among others a timer. It initializes the timer using common callback function:
...
- 639
1
vote
1
answer
354
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Atmega169PA interrupt source
Is there a simple way of determining which module causes an interrupt on an ATmega169PA? I have 3,000 units executing the same code and there were 10 units that executed my ISR(BADISR_vect) handler ...
- 11
1
vote
2
answers
3k
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Multiplexing AVR (ATMega328) PWM within Interrupts
I'm trying to take 3 common anode RGB LEDs and hook up the cathodes of each to three of the PWM outputs on an ATMega328p and then in an ISR, multiplex between them all. The problem I'm running into ...
- 1,623
1
vote
1
answer
896
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Simple AVR interrupts in C - How to cleanly stop and restart "INT0"?
I'm trying to use an ATTiny84's INT0 pin to detect a falling edge event on a 1 kHz signal.
What is the correct way to temporarily halt this interrupt INT0, and then resuming it at a later time, ...
- 249
1
vote
0
answers
696
views
Reuse I2C SCL or SDA Pins to signal interrupt
In an I2C network, I am using an AVR microcontroller (AtMega328p) as a Master and I hooked it up to multiple sensors as Slaves, such as the TMP102, SI1145, MPU9250, among others.
All of these sensors ...
- 155
0
votes
1
answer
2k
views
Atmega2560 Usart Interrupt problem
When I send any data from serial port, RX pins are flashing but ISR is not running.
Here is my code.
...
- 360
0
votes
2
answers
115
views
AVR MCU Interrupt toggle a LED problem with 100 extra toggle
I am playing around with an AVR MCU. I am having trouble toggling a LED. It's being toggled faster than I have expected. It should be toggling at 500hz, but it's up to 600hz and not very stable. I ...
user83582
0
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1
answer
82
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Thread-Style Operation on Microprocessor
This is a general question about designing firmware for AVR microcontrollers, say, the AtMega16.
I have a routine that I am running through several thousand times per second. The routine is entirely ...
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0
votes
1
answer
2k
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Atmega Microcontroller interrupt delay function on button press
I am using Atmega32A and I have 2 LEDs. Here's step by step what I want to do
When the MCU is powered, I have one LED lit (PC0)
When click on a button (PD6) the second LED at (PC1) is lit and the ...
- 153
0
votes
3
answers
1k
views
AVR-C turning led off after number of blinks with interrupts
so what I am trying to do is that I am trying to make the led blink for a certain number of times before it turns off. I want to avoid using delays so I tried
utilizing the interrupt and I also used a ...
- 77
0
votes
1
answer
226
views
UART doesn't transmit all characters when using UDREn interrupt
Note: I am beginner :) MCU: Atemega328p
In Method 1, I am using a UDRn data register empty interrupt once the transmit buffer is empty and inputting characters from ...
- 479
0
votes
2
answers
950
views
Modifiying variable inside of Interrupt vector. AVR
My question is again about modifying variables inside the ISR. If the variable used only inside of ISR, I don't have to declare it as volatile, right? After some researching, I figured out that ...
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0
votes
1
answer
2k
views
0
votes
1
answer
2k
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AVR Atmega8 USART and ADC and PWM
I have created 2 different PWMs using timer 1 and 2 on ATmega8, that is used to control a linear motor. I'm using a hall effect sensor to detect changes in voltage as the linear motor moves left and ...
- 623
0
votes
1
answer
320
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Faster Timer0 overflow than 2 ms on Attiny85
I'm trying to get a Timer0 overflow with an overflow every 500us, but can't find a solution to get it so low.
I'm running the Attiny85 on its internal 1 MHz clock, so I know it is not gonna be the ...
- 309
0
votes
1
answer
75
views
Problem or misunderstand of ADATE bit on ATTiny45
I have 2 buttons connected to pulled-down ADC input.
I want to trigger ISR(SIG_ADC) when ADC finishes conversion - this is working.
If I start ADC using ...
- 209
0
votes
1
answer
231
views
Error Real Time Clock implementation AVR microcontroller
I want to create a real-time clock using ATmega328p microcontroller.
The microcontroller's frequency is 1 MHz. So, I think I should use timer interrupts in CTC mode to generate interrupt every second.
...
0
votes
2
answers
2k
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Delay doesn't work (avr attiny 26, delay.h)
I am trying to learn how to write programs to microcontroller, and started with very simple things like LED blinking with given frequency, or controlled by button.
However, I have problems with using ...
- 103
0
votes
3
answers
201
views
How to get equal number of clock cycles before ISR on an AVR
While writing a time critical piece of code for an Attiny13, I figured I could use the rising edge of an input as a trigger to read in some self clocking data. However, the number of clock cycles ...
- 1,726
0
votes
1
answer
321
views
Saving the last value used in an ISR
I am using a level-triggered interrupt. During the interrupt OCR1A increases and the servo moves. I want to save each value of OCR1A when the pin returns to its previous level. So far I have only been ...
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0
votes
1
answer
119
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AVR32 goes to unrecoverable exception when exiting interrupt routine
I'm using an ATUC128D3 microcontroller and have 5 switches connected to it. I have the GPIO interrupt configured to trigger on a falling edge and this works just fine.
It enters the interrupt and the ...
- 397