From: David Wood (jbevren_at_starbase.globalpc.net)
Date: 2002-07-09 12:55:43
Even if the GAL is security-locked, you can trip each I/O line and see if you can get a dependable pattern. Could you glance at the underside of the pcb and detail what lines go where? It can help with some educated guesswork on how the gal's used. ;) -David On Tue, 9 Jul 2002, Nicolas Welte wrote: > Recently I got something that might be quite interesting: a small PCB that > boosts the Z80 in the C128 to 8MHz. It has the name Rossmöller on it, this is > the same company that made the C64 Turboprocess 4MHz card. > > The PCB has a GAL on it, and it has two wires: one gets the 8MHz dotclock > from the 8701, the other an 1MHz signal from one of the bus buffers (I guess > for synchronisation of memory accesses). The GAL also connects to the > previously unused Z80 signals that control memory access and wait states. So > it can run at 8MHz unless it needs memory access, while in the original C128 > it uses 4MHz during one half of a 1MHz cycle (does anyone know if it can use > both 1MHz cycles in fast mode?). > > I'd like to run some Benchmark tests on this thing, are there any standard > programs for CP/M I should use? > > I also need to get that GALBlast built (have all parts already), maybe the > GAL isn't security fused and I can read it out. > > BTW, I have a picture of the device online: > http://people.freenet.de/x1541/z80.jpg > > Nicolas > > Message was sent through the cbm-hackers mailing list > Message was sent through the cbm-hackers mailing list
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