raisinland

Nice, I'll look into a PC supply if my solution has any problems.

Just built an adapter for an Adam computer off ebay. Wanting a efficient but cheap adapter I set about making one.I got a couple cheap 12v 1A switching supplies and a 5v 3A off ebay. A switching 5v inverting supply (TPS6735) off digikey and some parts from my local electronics shop and the below is the result. The small circuit board was built from the schematic in the inverting supply datasheet. Benefits: Switching 5v and 12v supplies are cheap and plentiful. You can use them for other things if not using the Adam. Drawbacks: taking up three outlets, one could get confused and plug 12v into the 5v jack. I used two separate 12v supplies as the data drive and logic 12v lines need to be separate. It works on games and the typing program loads but I haven't been able to try the data drive as I don't have a keyboard.

Cool! Thanks for checking this out. It would seem this means just doing the sign update on low-byte writes isn't the proper way to fix Stun Runners. Interesting about the AB values, I don't see an obvious pattern either.

Would these make sense? Test zero treated as negative: write zero to D,C registers (should set sign flag) Write 1 to D register (sign flag should remain set due to setting low byte only) Write 2 to B, 0 to A result should be negative according to the documentation. test 0x8000 treated as positive: multiply 0x8000 and 0xfffe, result should be negative.

I got it working the same way Handy does, but Mess focuses on hardware accuracy so I'd like to have the multiply behavior be as close to the actual hardware as possible. Where is the best place to get a BLL loader cartridge (I'm in the US)?

Yeah, I'll help out as much as I can. I have a lynx II for testing. Do you have a Lynx or flash cart?

The Lynx documentation states that hardware multiply has a sign error (0x8000 is treated as positive, 0x0 as negative). Has this ever been verified on a real Lynx? I'm working on the Mess driver, and with the sign bug implemented Stun Runner doesn't work. Handy initializes the math registers to 0xffff and updates the sign flag on writes to the low byte of the math registers. This fixes the problem but I'd like to know if this is actually what the lynx does. I'm considering getting a flash cartridge and learning enough Lynx programming to test this but i was hoping somebody here would have the answer.