Re: Asteroids Vector RAM Read/Write Problems

From: Dave Langley <dave2084.forums_at_googlemail.com>
Date: Sun Jan 30 2011 - 13:57:41 EST

On 25 Jan 2011 7:37pm, Mark Shostak wrote:

Just out of curiosity, how did you confirm the rams are good?

Easy, they're all socketed ... so I replaced them with new ones, but the removed ones were also fitted to another board and confirmed working.

 Also, how did you confirm the rams are being selected?

I looked at the signals on Pins 8 and 10 of the RAM chips and all seems well, I guess I need to compare them to a working board. I'm at the point now that it must be /VW (pin 10) or CS (Pin 8) but I'm completely stumped.

I have also physically confirmed the sockets and traces are good for the Address/Data busses from the Vector ROM.

I spent so long looking at this board and decided to pick up a basked case one which is almost working now (see my other post for details).

-- 
Dave Langley

--------------------------------------------------------------------------- ** Unsubscribe, subscribe, or view the archives at http://www.vectorlist.org ** Please direct other questions, comments, or problems to chris@westnet.com Received on Sun Jan 30 13:57:49 2011