I have been lurking and following for a few years. This will be my first post. I would like to say rusefi open source platform has been great for the diy tuning efi community.
I have considered spinning rusefi board with pnp connector for obd1 honda. However most folks seem to be perfectly content with modified honda rom and using one of the available options for a daughterboard to do real time programming. Hardware can be had from moates,hondata,or cobrartp. Hondata software can only be used with their hardware. Honda tuning suite, EcTune, Neptune,BMtune,crome are all software options .
Honda tuning suite is a free and powerful program for anyone to use.
To this day there is not any open source options for an eeprom emulator to enable real time tuning function. I have designed a board for 27c256 or 27sf512 eeprom emulation. This device is intended for use in obd1 honda for me. It also could be used in Motronic, Jetronic, Siemens MS40.1, GM, DSM (BMW, Audi, Porsche, GM, Mitsubishi, Fiat, Volvo, etc.). I would like to share this design public so anyone with soldering skills can order a board and assemble it.
I am posting to seek help in writing firmware for it I have little to no experience in software development. The mcu is atmega64a. 2 sram chips 128kx8 ly621024ll-55. 2 channel uart ftdi ft2232d. The moates ostrich and xtronics romulator both have open hardware protocols. I would like our device to use moates ostrich and or romulator protocols as to allow easy integration with existing tuning software's.
I am posting from my mobile phone right now. I will update post shortly to include schematic and hardware protocols.
![Image](https://i.imgur.com/6shDZWi.png)
![Image](https://i.imgur.com/w32O6mj.png)
![Image](https://i.imgur.com/w32O6mj_d.jpg?maxwidth=640&shape=thumb&fidelity=medium)
updated 11/25 with schematic and hardware protocols for anyone who would like to review and give feedback/support.