ATmega168 documentation uses word addressing, avrdude uses byte addressing

I was programming USBaspBootloader into a metaboard with an Atmel AVR ATmega168 microcontroller. I always got this error: usb 6-2: device descriptor read/64, error -71 … usb 6-2: device not accepting address 21, error -71 1. USBaspBootloader’s Makefile specifies atmega168 and BOOTLOADER_ADDRESS=3800 by default. This is in hex addressing a byte, i.e. 0×3800. avrdude uses [...]

Atmel AVR timer/counter examples

Here’s the catch: the timer/counter is capable of operating on a completely hardware level, no software interaction required. A nice explanation is given here (section 2). This page starts with an introduction using a software counter. Which shows how tedious that is, especially counting the clock durations yourself. Another page at AVRfreaks here deals exclusively [...]

Atmel’s assembly: branch to address, not label

Say you had this code to wait for n iterations, where n is stored in register arg. You could write: wait: dec arg brne wait ; step back to dec ret Which would be OK. But if you didn’t have that much free registers, you would probably pass n using the stack. In which case [...]

Trusted computing will make me distrust my computer

This is old news that got happily shoved away and forgotten. And Atmel’s at the forefront, too, wow. Fuckers. Time to stop upgrading your hardware and start downgrading. Time to stop listening to RIAA. That’s right, the RIAA are the authors, not the artists, and they suck. You have been giving them too much free [...]

Making my own USBasp programmer

I’ve been trying to make some for the last two weeks (yes, two weeks). I didn’t use the provided designs, that’s why it took so long: first, I wanted to get apprehended with the UNIX electronics CADs; then, as one should expect, I ran into design trouble of a layout that hasn’t been tested. So [...]

First tryout of AVRs

I bought a few programmers some time ago. On eBay, for around 16 dollars american. They’re a copy of Thomas’ Fischl’s USBasp. Now I’m toying around with them – a part of my summer internship. First off, I tried connecting one working programmer to the other and see how it goes. Well, FreeBSD couldn’t recognize [...]