Recent content by igowen

the only thing i noticed in the photo is that C12 is wonky and one side of it might not be in contact with the pad on the PCB, but i kind of doubt that alone explains any of the issues you have.

the CPU walking the bus is a really good sign -- a lot of things have to be going right for that to happen. UK6 is the video ROM, right? pins 2-10, 21, and 23-25 are just the address lines (i.e., inputs) so i wouldn't expect swapping the chip to affect anything there. i'm assuming that you're...

one thing to try would be to pull the ROM and check the address lines with a scope -- if the CPU is running you would expect to see A(2) through A(31) being pulled high/low (square wave, basically) in exponentially decreasing frequency as the CPU is trying to find some code to run. if that's not...

thanks! it is very much still working, and i've got the Bolle trinity (ethernet+040+cache) in there speeding things up. i also picked up a radius video card for the IIsi that i'm trying to fit (it works but i haven't tried to get the case back on yet, and i need to build the internal cable to...

very interested in this! i had this issue with a radius pivot card in my SE/30 -- the color was very washed out on my beater Dell LCD monitor with a regular mac-to-vga adapter like you have. i ended up "fixing" it by buying a monitor that supported sync-on-green :P but it would be nice to have...

i was in your shoes (exact same symptoms) for a frustratingly long amount of time with my build. the root cause in my case did turn out to be poor connectivity on UH7, so that's probably where i'd start. specifically make sure that you're getting the expected clock signals out of the chip (C32M...

hi all, just wanted to share my (by all appearances) successful build. I got my first successful boot (off of a real floppy, no less) last week after spending a couple of frustrating weeks tracing out address and data lines trying to figure out why i was still getting a Simasimac pattern on...