Questions tagged [avr]
AVR is a 8- and 32-bit microcontroller core developed by Atmel. AVR was chosen as microcontroller for the first generations of the popular Arduino SBCs.
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AVR: Usage of Force Output Compare bits
Currently I'm dealing with Tiny2313 for my project. Timer runs in CTC (WGM12) mode so OCR1A is used to set TOP of the timer. I want to use OCR1B to generate output signal.
In documentation is ...
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How to get an ENC28J60 to work?
For starters: Yes I know I'm about to reinvent the wheel with the following task ahead.
I want to create my own library for the ENC28J60 for an AVR (ATMEGA1284P).
So I've been browsing the net for ...
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PID H-bridge random current spikes
My H-bridge consists of 4 n-channel MOSFETs. The high side is driven by a basic bootstrap circuit, and the low side is directly driven from the MCU.
Using a PID function to control the motor by its ...
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Minimum circuitry for robust operation of the "new" ATtinys (1614) with Optiboot
I have spent hours now trying to catch up on the replacements for the old ATtiny's, there does not seem to be a robust (meaning, with protections that we could find in an UNO or Mega for example) ...
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ISR won't modify a global variable (IAR)?
First, some background on what I'm working on.
I have a custom board with ATmega324A that I designed as part of a project I'm working on. Originally, software for the uC was written for GCC in Atmel ...
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Why accessing the SRAM is slower with AVR XMega load instructions?
The AVR XMega has 16 GPIO registers in I/O space in addition to its internal SRAM. Interestingly the timing of LD instructions differ to these locations: Accessing the (rather large) I/O space is ...
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What Is the Best Way to Debug an AVR Microcontroller Using the Command Line?
My AVR programming method is usually as follows:
compile the source code with avr-gcc:
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Configuring the Ports of an AVR Microcontroller for SPI Use
I am trying to configure the an ATtiny84A for use with SPI, but I have some confusion with what Is being said in the datasheet for configuring the ports. The ATtiny84A has, what the datasheet calls, &...
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MAX7221 not always powering on
I have a MAX7221 SPI 7-seg. LED driver linked to an AVR168P microcontroller.
Sometimes when powering on, everything works as expected. Other times the display blanks and remains blank. Other times ...
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Deployoing compiled program from Atmel Studio or Avr dude to Atmel "XMEGA-A3BU Xplained"
Im attempting for the last 3-4 days to connect the Atmel dev board to the computer in order to either load the .elf or hex file to the bootloader in order to turn on a LED.
Im following instructions ...
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Atmel XMEGA PDI Issue
I have an Xmega chip I've been using for a year and had no problems with the PDI interface programming it with the Atmel-ICE debugger/programmer. The problem is I accidentally connected the cable to ...
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DRV8711 SPI mode
I'm facing some problems with SPI bus of DRV8711 (http://www.ti.com/lit/ds/symlink/drv8711.pdf). Repetitive reads of the same register give the same values but the communication doesn't seem reliable.
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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 ...
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ATtiny85, timer 1B does not work if COM1A1|COM1A0==0
I read the datasheet, and checked http://www.avrfreaks.net forum, but I cannot understand why on an ATtiny85:
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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) ...
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