#AVR #ISA calling conventions for GCC: R2–R17, R28, and R29 are “call-saved”, plus implicitly R1, which has to always be kept 0.
on 02026-09-11Apparently #Arduino ATMega328 #AVR #microcontrollers can sample at 38ksps if you set the ADC clock divider to 32 (16MHz ÷ 32 = 500kHz, and then you need 14 clocks per sample), and still have an ENOB of about 9.5. Not exactly high #precision #electronics but often adequate. And if you’re willing to accept more noise you can do 76ksps with an ENOB of about 8.7. Higher sample rates produce audible clicks when used for audio.
on 02026-09-09#Contiki already ran on #AVR #microcontrollers in 02004 and supported #VNC on them.
on 02026-05-11#Arduino (#AVR) preemptive multithreading operating system. Looks abandoned 8 years ago. #operating-systems
on 02025-08-23#PDF from 02019 by James Brakefield listing mostly open-source #microcontrollers #gateware on #OpenCores, including a bunch of #6502 designs, an RCA 1802 or two, some Motorola 6801 clones, a bunch of #8051 clones, several #8080 designs (including one by C.H. Ting!), several #68000 designs, several #68HC11 designs, several ARMs (which are not all proprietary), some #AVR designs, a lot of #Forth chips, a PDP-1, a bunch of MIPS designs, an MMIX, various #OpenRISC 1000 designs, a PDP-10, a bunch of PDP-8s, a lot of PIC16s, a lot of #RISC-V designs, Cray-1 and Cray-2 clones, several Z80s, the #Reduceron, etc. There’s a table specifying how many LUTs each one achieves, how many KIPS per LUT (!), what they’re written in, how big their address spaces are, year started, year of last revision, etc.
on 02024-08-25Another #bitbang #USB implementation for #AVR derived from #V-USB
on 02024-01-25another #bitbang #USB implementation for #AVR
on 02024-01-25"V-USB" is a #bitbang #USB implementation for #AVR
on 02024-01-25Atmel’s appnote on #audio playback on #AVR using SPI Flash #hardware
on 02024-01-23yeah, it’s not #AVR #speech-synthesis, it’s “#Audio encoded as unsigned 8-bit, 8kHz sampling rate,” 4.6K of it
on 02024-01-23#speech-synthesis on an ATtiny85 #AVR? or just #audio reproduction maybe with a piezo buzzer
on 02024-01-23#speech-synthesis on an ATtiny85 #AVR? No
on 02024-01-23how to connect #Arduino as ArduinoISP to program an #AVR ATtiny45
on 02024-01-23how to connect #Arduino as ArduinoISP to program an ATtiny45 #AVR
on 02024-01-23#AVR #Arduino UNO #hardware #pinout #CC by-nd
on 02024-01-23#lcamtuf on #microcontroller #electronics driving #SSD1309 #LCD #hardware with an #AVR
on 02023-01-24#Linux on #AVR #hardware by running #ARM #emulation ("μARM") in the AVR, achieving about 0.01 MIPS
on 02021-01-24whoa, XTEA #crypto in 504 bytes of machine code on the #AVR! Plus lots of other things — I didn't know you could do AES in 2½K.
on 02017-06-14#OctaPentaVeega #AVR shield photo
on 02017-05-29#OctaPentaVeega #AVR #demoscene source code, cc-by-sa
on 02017-05-29#video of a #demoscene production on #AVR #microcontroller #hardware generating color VGA signals on three ATTiny85 chips run off a common clock, driven from a 9600 baud serial signal, "OctaPentaVeega" cc-by-sa
on 02017-05-29Atmel #appnote #PDF on driving stepper #motors with an #AVR
on 02017-05-19reducing #Arduino power use to be able to last a year on a coin cell: use a Pro Mini, disconnect the power LED, bypass the regulator, and spend most of the time in power-down sleep mode with the brownout detector off, using Rocketscream’s LowPower library. #AVR #hardware
on 02017-05-19And #Arduino Nano #AVR #hardware has #pricing of AR$91 (US$6).
on 02017-04-14However, ATMega328 #AVR #hardware in a 32TQFP package has #pricing of AR$120 (US$8). Also that’s in Mendoza.
on 02017-04-14Another Mercadolibre vendor sells ATMega328P-PU #AVR #hardware with #pricing of AR$45 (US$3).
on 02017-04-14#radio #hardware using an #AVR to generate a square wave and carrier wave and a 2N7000 MOSFET to amplify the carrier wave and modulate it with the square wave.
on 02017-03-31measuring #AVR #hardware supply voltage against the internal bandgap voltage reference allows you to indirectly measure external voltages against that reference.
on 02017-03-30explanation of #AVR #hardware serial programming with the SPI bus, the most normal non-Arduino way to do it
on 02017-03-28using #Arduino #hardware for in-system programming of #AVR chips with the serial protocol
on 02017-03-28Joonas Pihlajamaa used an ATtiny2313 #AVR and a USB/serial converter as a low-speed (50 ksps) logic analyzer to debug his PS/2 keyboard #hardware interface.
on 02017-03-22simavr does #AVR #emulation with timing and dumps out #VCD files, a sort of built-in virtual logic analyzer. The instructions in the README here produce somewhat less debugging output than shown in the current version of simavr, and it took me a while to figure out how to open them in gtkwave, but they do work. Also the VCD format, which sigrok supports for both input and output, seems super simple.
on 02017-02-23#PDF #paper “NaCl on 8-Bit #AVR Microcontrollers” requires 23 million cycles to Ed25519-sign, 32 million cycles to verify, 268 cycles per byte for symmetric Salsa20 encryption, 195 cycles per byte for Poly1305 authentication, all in under 18 kB of code and 1.4 kB of stack; all constant-time. #crypto
on 02017-01-14A tiny Lisp computer on #AVR #hardware in 16K of RAM using a PS/2 keyboard and a little OLED display.
on 02016-10-19#CPM on an ATMega88 #AVR with external DRAM and an SD card. Slow, takes 30 seconds to boot. The #Z80 #emulation is somewhat incomplete. Still, a super fun #hardware project.
on 02016-10-10How to read and write the Flash on an #AVR
on 02016-10-10Jack Eisenmann’s Duo Binary runs on an ATTiny84-20PU #AVR with 128K of SRAM and 2MB of Flash #hardware. Six-bit binary character code, short pulse for 0, long pulse for 1. Has a filesystem browser, text editor, calculator, and number guessing game. #smallisbeautiful
on 02016-10-10someone complains that #JTAG on their #AVR ATmega2561 #hardware didn’t work at clock speeds over 300kHz, but it turned out to be a problem with the 7.1d version of their JTAGICE mkII firmware.
on 02016-07-13dude, you can see which #microcontroller chips Digi-Key has the most in stock at the moment! Which is probably a pretty good proxy for which ones are the most popular. #1 is a surface-mount ATMega328(-MU) at the moment, as is #5, while the spots in between are taken up by Freescale 8-bit micros (MC9S08SG32, of the HCS08 family, the successor to the 68HC08 and the latest in the lineage of the 6800, running at 40MHz, with a kilobyte of RAM and 16K of flash). #6 and #7 are 42-cent PIC10s, and then there’s an ATTiny85 and more #AVR micros until #14, which is a five-dollar MSP430. #hardware
on 02015-11-09#interpreters for #microcontroller (e.g. #AVR) programming languages, including amforth, which needs only 150 bytes of RAM. #smallisbeautiful
on 02015-08-05#AVR #modem using short and long pulses for 12 kilobit per second #audio data transfer, avoiding heavy-duty #DSP.
on 02015-08-05