Re: [Altair Computer Club] Re: Debugging Turnkey board autostart
- On 7/10/2010 1:25 PM, Steve Piette wrote:
> Results to follow.I received a good TURMON EPROM from Steve Shepard and after what seems
like a thousand years my Attache is now working again.
There were multiple problems, documentation errors, and ultimately a bad
CPU board. I fixed the auto start circuit but my EPROM was completely
erased after all this time. The Attache manual was correct that the
monitor EPROM needed to be installed in socket K1 not J1 as stated in
the Turnkey PROM Monitor Users Guide. I'm using the original version of
the turnkey board without the 88-SYS CLG mods.
The PROM switches needed to be set to 176000 (0xFC00)
The RAM switches set to 174000 (0xF800)
The Start switches to 176400 (0xFD00)
The SIO switches to 020 (0x10)
The Attache video board uses TTL level signals between it and the
turnkey board at 9600 bps.
Jumpers K2-P2, K3-P3, K4-P4, X2-X3, S0,S1, and S2 installed on the
Jumpers S-B, SW-SA, and M1-M2 also are installed for use in the Attache.
I'll have to figure out what's wrong with my other CPU board at some
point but getting the machine running again has got me smiling.