Hi
I have damaged gould 7200 scope - Its start and hold on Truetrace screen, I replaced leaked battery and repair damaged trace on PCB. Holding keys plot and hold all not work because system not scan keyboard. When I measure adres bus with scope probe, I accidentally connect A16 and A17 and program start. This combination work to force start. In first time scope make auto calibration, next start normal. RTC and settings memory work properly. All channels work, DSP and trutrace function work, printer work, all keys ok. Not work storing function - in any option ( RAM disk, Floppy or HDD) i have "no disk in drive" message. If I try format FDD or HDD some internal error are displayed.
When system stop on start logo - all adres and data bus are stop - no any activity, /Hold cpu signal are HIGH. Short circuit start method probably skip some program area.
When I can found EPROM dumps?
This scope can start without added HDD controller?
I thing its a problem with driving F82C721 because this hip control floppy and parallel printer port, floppy not work and If I change
plot device to parallel and pres "plot" key - the screen freeze and all activity on data/addres bus stop. On Enable pin of F82C721 I can see any pulse during startup or print operation. If I change Print to serial or GPIB, system still work and I see single pulse on
GPIB enable controller.