Thanks Ruud, and great news on the 8088 board too. Does it look like something folks would be able to duplicate? Are there any really hard-to-find chips on there? - Bo > -----Original Message----- > From: firstname.lastname@example.org > [mailto:email@example.com]On Behalf Of firstname.lastname@example.org > Sent: Monday, February 25, 2002 2:31 AM > To: email@example.com > Subject: RE: C128 repair advice... > > > Hallo Bo, > > I can give some other advices. By tying the WAIT-input to GND you stop the > Z80. AFAIK the Z80 immediatly starts at address $0000 after a > reset. As the > Z80 doesn't do anything at all now, you can use a digital > Voltmeter to check > the state of various address- and controllines. Including those > of a buffer > as Richard suggested. > > A step further is disabling the Z80 by pulling BUSRQ Low. Now you can feed > the address- and other lines with your own signals and see if the PLA, MMU > and other ICs work as they should do. > > > FYI: the 8088 board has been "schematiced" for about 75%. > ___ > / __|__ > / / |_/ Groetjes, Ruud > \ \__|_\ > \___| http://Ruud.C64.org > > > > Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing list
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