Questions tagged [fuse-bits]
Fuse (and Lock) Bits are a type of low level programming and security feature on embedded devices. Most popularly known in Atmel AVR devices, they can be likened to a secure Bios on a computer. They can also be found in MSP430, PIC, and other microcontrollers. Care needs to be taken when working with programming Fuse Bits, as they can render a device useless. MANY are One Time Programmable.
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Why did fuse bits successfully reset using ICSP and USBASP programmer?
I read a lot about fuse bits in AVR microcontrollers and everyone says that fuse bits can be reset by using high-voltage programmer only, they can't be reset via UART<->ICSP.
So, I've received ...
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AVR ATmega328P wrong fuses set
I was programming on the AVR ATmega328P using the USBasp programmer. I uploaded the blink example but the LED was not blinking. Thus I went on changing the fuse bits to the one Arduino has. During ...
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AT90USB1286 bricks after disabling clock divider
I have an AT90USB1286 which is connected to a 16MHz external crystal oscillator. It is my understanding that by default from the factory the CKDIV fuse is enabled which makes the chip run at an ...
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External RC oscillator fuse programmed instead of external crystal fuse
Is there anyway to revive an Atmega8A? avrdude says avrdude: error: program enable: target doesn't answer. 1 ever since I ...
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ATtiny2313 external 2 MHz crystal
I would like to run my ATtiny2313 from an external 2 MHz crystal, but I'm unsure how. I have seen images and examples where there are capacitors connected to ground after the crystal. Like this:
But ...
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How to securely lock 100% a microcontroller like ESP32 or ATtiny85 or any other ATtiny?
I have been doing research on how to securely lock and prevent 100% from someone seeing my code.
ESP32 can be "hacked" see here.
ATtiny has fuse bits that can be set to protect the code but ...
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Help With ATMega32 Fuses
I decided I wanted to learn Atmel Studio to be able to work with all their microcontrollers problem being i'm trying to use a brand new ATMega32 with default fuse settings and an external crystal ...
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Why does my Atmega328 clock seem to be off by a factor of 2?
I have an Atmega328 chip I am trying to debug. I have a sketch that blinks an LED and echoes back things received over the RX/TX pins. I am using the "Import Arduino Sketch" feature in Atmel Studio 7. ...
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atmega328pb mcu gets bricked after uploading bootloader
i have a strange problem, maybe this post will be long, but i try to give all the details:
i’ve designed a pcb with smd components, around the atmega328pb mcu. it uses an external 16mhz clock and has ...
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Recovering a program from a locked AVR [closed]
How can a program from an AVR be recovered when its lock fuse bits are set?
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ATmega stopped working after changing CKDIV8 fuse
I have ATmega32U4. I connected it via SPI programmer and in Atmel Studio I have read their signature properly. It was working. Then I cleared and programmed CKDIV8 fuse. Clock was set to internal RC. ...
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How to test a CPU watchdog on board?
The watchdog of an ATMEL ATXMega128 should have been enabled with fuses. It triggers a reset, if the timer was not reset within the configured time span.
I want to be sure, that it is enabled and ...
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ATmega328P 16MHz or higher clock output on CLKO pin
I need a high frequency clock (16MHz or higher) to drive OV7670 camera module, and I want my ATmega328P to be source of that clock. I'm using the CLKO pin since I ...
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Fuse Bits for ATmega1284P
I need to use an external crystal oscillator for PWM generation on the ATmega1284P. I have set the wrong fuse bits and I can't program it now. Can this be rectified?
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Which crystal do i choose in atmel studio?
I'm trying to use this 16mhz crystal with an atmega328 chip and I need to set the fuses for it in atmel studio. But I have no idea which option is the correct choice. None of them say 16mhz.
I've has ...
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