Diagnosing and attempting to fix a Yamaha DX100 – Part 4

I decided to have one more look at the data pins, largely inspired by this oscilloscope trace from part 3. I figured if the address and select pins were working (yellow, cyan and purple) what could I do to try to work out what is driving the data pins (darker blue) wobbly... And no, after … Continue reading Diagnosing and attempting to fix a Yamaha DX100 – Part 4 →

Diagnosing and attempting to fix a Yamaha DX100 – Part 3

At the end of part 1, I've established that the basics all seem ok (PCB, interconnections, power) and that basic digital logic stuff is happening. In part 2 I checked the ROM, reflowed a number of the solder joints, and started to look at the connectors between the main PCB and the LCD, but still with … Continue reading Diagnosing and attempting to fix a Yamaha DX100 – Part 3 →

Arduino EEPROM Reader PCB Build Guide

Here are the build notes for my Arduino EEPROM Reader PCB Design. Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments! If you are new to Arduino, see the Getting Started pages. Bill of Materials Arduino EEPROM Reader PCB (GitHub link below). 2x … Continue reading Arduino EEPROM Reader PCB Build Guide →

Arduino EEPROM Reader PCB Design

This is a PCB version of the Arduino EEPROM Reader/Writer as described here: https://github.com/beneater/eeprom-programmer but with slight adjustments to support reading of 27Cxxx style ROMs often found in vintage equipment. Build Guide here: Arduino EEPROM Reader PCB Build Guide. Update: Since developing this board, I've found a much more comprehensive DIY board here: https://github.com/TomNisbet/TommyPROM. The documentation … Continue reading Arduino EEPROM Reader PCB Design →