Sunday, February 26, 2017

Wrote a custom analyzer for Saleae Logic 16

Trying to troubleshoot Star Rider was hard enough without trying to decode the laserdisc commands "by hand."  I wrote a custom analyzer for my Saleae Logic 16 to decode the commands automatically:

Tuesday, February 21, 2017

Star Rider : Playing a 1984 piece of hardware with an xbox 360 wireless controller?

It started innocently enough... the 'DISC SEARCH' test wasn't working and I wanted to fix this.  Eventually, I ended up creating a custom PCB in conjunction with an xbox 360 wireless controller just to get the dang test working :)

I use a (IMO) very cool troubleshooting technique involving the ROM program disassembly and a logic analyzer to track the issue down.

Monday, February 13, 2017

Hacks to troubleshoot Star Rider controls I/O problem

Warren hacked up an Arduino to allow a playstation 2 controller to hook up to Star Rider.  I am having trouble getting this working, so I reprogrammed the Arduino with the original PS2 example code which uses serial output to show what's going on.  The only problem is I don't have a USB to 5V TTL adapter.  So I thought about what I did have.  I had a Papilio One FPGA dev board with a USB connection on it.  I could program the FPGA to just pass the RX/TX signals through two of its I/O pins.  However, this uses 3.3V, not 5V.  So I couldn't just plug it directly into the Arduino.  I needed something to shift the voltage level.  Then I remembered my Disk ][ breakout board which I hadn't yet soldered up.  This board does exactly what I need!  So I ended up hooking the Arduino up to the Disk ][ breakout board to convert the 5V TTL to 3.3V TTL and then hooking that up to my Papilio One which is hooked up to my desktop.  It works! :)

Saturday, February 4, 2017

Fixing Steve Bower's PIF board

I made a new 25 minute video showing me troubleshooting and eventually fixing a problem with Steve Bower's Star Rider PIF board, after going down several wrong paths.

This hardware is incredibly difficult to keep running :)