At28c256 programmer This repository describes a simple open-source programmer for the 28C256 32kB EEPROM memory. bin file with python, send it via serial to the Arduino nano and write it to the eeprom a byte at a time (kinda slowly tho, the limit is a byte every The code in /eeprom-programmer is the basic programmer that programs a few bytes into the EEPROM and dumps the contents. Hello, I'm building an 8-bits computer with old cpu (for educational purpose). This beauty is able to open a . g. Its 256K of memory is organized as 32,768 words by 8 bits. . AT28C256 1. I'll be short since I already put everything on my GitHub. Jan 6, 2019 · An Arduino-based Programmer for AT28C64/AT28C256 EEPROMS. com/beneater/eeprom-programmer Software All the code is available at GitHub, in my 28c256pgm repository. make flash will try to write the code to microcontroller using avrdude with usbtiny compatible programmer Oct 21, 2019 · $ . The address bus of the EEPROM (up to 15 bit) is controlled via two daisy-chained 74HC595 shift registers using hardware SPI @ 8 Mbps. Description The AT28C256 is a high-performance electrically erasable and programmable read-only memory. Oct 29, 2025 · Tested with chips from several manufacturers including Atmel AT28C256, Xicor X28C256, and CSI CAT28C256. That software, along with the EEPROM programmer’s hardware are described in detail in the following video. The SDP feature seems to be a leading cause of problems for people trying to program these chips with Arduino or other homebrew hardware. Looking at Atmel parallel EEPROM AT28C256 (32 KB), I read in the datasheet AT28C256 Description The AT28C256 is a high-performance electrically erasable and programmable read only memory. Oct 29, 2025 · The 28C series parallel EEPROMS, like the 28C256, support fast block writes and algorithms to implement Software Data Protection (SDP). For building you need a working make, avr-g++, and avrdude. It is heavily based on Ben Eaters EEPROM Programmer https://github. This is a good place to start if you’re looking for the fastest way to make sense of this repo: Build an Arduino EEPROM programmer. A python3 code is provided as a terminal-based interface. Manufac-tured with Atmel’s advanced nonvolatile CMOS technology, the device offers access times to 150 ns with power dissipation of just 440 mW. 6502 or Z80 processors based computers). Also works with the smaller 28C64 and 28C16 chips, although some parameters may need to be adjusted. /eeprom. But I don't have any *PROM programmer. Now, to make it work, I need a ROM that I will fill with all kinds of stupid or smart code. I have only built the project on OSX, but the makefile shohuld directly work on Linux too. Building Just type make, and you should get hex and eep files. The data bus is controlled directly via the pins of the ATmega. Address and data bus are Hello everyone! Today I'm posting about my latest creation (it took 2 months tho), an Arduino powered EEPROM programmer, specifically made for the AT28C256. To read a single byte: EEPROM writer for AT28C256 using Arduino Mega Quick and dirty breadboard circuit and Arduino sketch to make possible write in the AT28C256 EEPROM Programming the AT28C64B or AT28C256 EEPROM chip with an Arduino Mega - crmaykish/AT28C-EEPROM-Programmer-Arduino The heart of the EEPROM programmer is an ATmega8 microcontroller. The programmer can be controlled directly via the Arduino serial port. py AT28C256 EEPROM Programmer Read or write individual addresses, dump out the full contents to a file, or load an image file onto the EEPROM. The device has been thought as an affordable tool to aid the hobbyist in the development of small 8-bit computer projects (e. ivjk iked qguklbip ksqu ftdo awz ppawqurp lwqohe grz vru