Found some of it: http://members.cox.net/seanriddle/willy.html ----------------------------------------------- The classic Williams games cram 48k RAM, 48k ROM and 4k I/O into the 6809's 64k address space using bank-switching. $0000 - 8fff is bank-switchable between RAM and ROM. Writes always go to RAM. $9000 - bfff is always RAM. $c000 - cbff is I/O $cc00 - cfff is CMOS RAM; $cc00-ccff is write-protected when coin door shut. $d000 - ffff is always ROM * ------------------------------------------ Now where was the toggle bit to enable set the bank for the RAM? That is there somewhere...as I say it's at the shop with my schematics etc...sorry... John :-#)# At 01:32 PM 10/11/2002 -0500, Kev wrote:
Well my biggest problem is the Williams video boards of the early 80s. If you put the 9100 in auto RAM test mode this will fail because (I'm guessing here) that it isn't properly writing & reading from the 2nd page of the RAM & higher.
If you manual do 2 writes & 2 reads it works fine but the auto test cann't handle it.
There is a big write up in the 9100 Application manual specifically on handling Dynamic RAMs but I figured I'd solict for a bit of insight first.
Thanks, Kev
I don't see how testing dynamic would be any different than testing static, both look the same to the CPU....if you want to test the individual ICs then you need to pick up a BugTrap Dynamic Ram tester...or similar that will check the old timers.
You can replace dynamic with static if you are so inclined with just getting the addressing and select sorted out. Static ram is much faster now than it was back in the 70/80's and can easily do the job.
Or do I not understand the problem you are proposing?
John :-#)#
At 09:08 AM 10/11/2002 -0500, Kev wrote:
Has anyone built any programs to do Dynamic Ram test for either the 9010 or 9100?
I'm looking for something that would cover 4116 &/or 4164s.
Thanks, Kev