[comp.sys.amiga.emulations] Bridgeboard + Fast Memory?

davem@hp-lsd.COS.HP.COM (Dave K. Martin) (03/08/91)

This may be a dumb question but I've never seen it asked or answered so here
goes.....

Why is 6-meg of fast memory the ideal configuration for a system with a
bridgeboard?  Does it have to do address contention on the Zorro buss?

This is of some concern because I have an XT bridgecard and a Microbotics 
8-up with 6-meg along with 1-meg of chip ram on the motherboard.  What happens
if I add another 2-meg to the 8-up card?

This may be a moot point as my Mega-Midget-Racer is due any day now and any 
new memory added in the near future will be 32-bit memory :-) 



Thanks....
dave





 Another dumb question brought to you curtesy of (insert favorite flamee here)

peterk@cbmger.UUCP (Peter Kittel GERMANY) (03/15/91)

In article <32790001@hp-lsd.COS.HP.COM> davem@hp-lsd.COS.HP.COM (Dave K. Martin) writes:
>
>Why is 6-meg of fast memory the ideal configuration for a system with a
>bridgeboard?  Does it have to do address contention on the Zorro buss?
>
>This is of some concern because I have an XT bridgecard and a Microbotics 
>8-up with 6-meg along with 1-meg of chip ram on the motherboard.  What happens
>if I add another 2-meg to the 8-up card?

Problem is, you only have 8 MB autoconfig address space. Normally a RAM
card is configured before a bridgeboard, so after configuring this RAM
card, all available address space is already given there, and nothing
remains for the bridgeboard, which also needs some space (was it 512 KB?).
So your bridgeboard wouldn't be able to autoconfig, and thus remain
sleeping, plainly not useable, sad...

-- 
Best regards, Dr. Peter Kittel  // E-Mail to  \\  Only my personal opinions... 
Commodore Frankfurt, Germany  \X/ {uunet|pyramid|rutgers}!cbmvax!cbmger!peterk