#CSA '020 comp w/2 megs
4 messages in this thread
I have a CSA piggyback board with a '020 and 68881 plugged into my machine.
Recently I have trying to purchase a 2 meg board to use with it. I have tested
4 boards and have found only the COMSPEC board to fuction. This is a problem
because it is very expensive and hard to find.
Both the Microbotics board and the RS Data System board go into a terminal
rebooting just before displaying the screen to insert the Workbench disk (1.2)
and while in 1.1 will get into workbench but will crash or error when trying to
configure the memory with ADDMEM. I also tried the EXPANDER II by cypress and
keep getting GURU Med. errors indicating an Addressing problem.
Has any one had experience interfacing Mem with the piggyback board or have any
expanation for the problems. I have contacted a couple of the companies and
they are looking into the problem, but i would apprech. any additional help
Paul Hart
I've never tried the CSA board with or without external memory, but I can guess
at a few possible problems it might be causing. (1) Bus loading: The 86 pin
connector on the side of the Amiga is speced to be able to supply 1 "F" type
load on each output pin. If the CSA board is presenting any unusual load to
the unbuffered 68020 outputs, this may be causing problems. (2) Buffering:
Does the CSA board buffer anything coming from or going to the 68020. I
suspect that it does. This could cause some timing problems with the external
boards. Some of the Amiga's bus timings get pretty critical. (3) On-Board
Memory: Does the CSA board have any memory or other item on it that might have
to be placed in Amiga memory, say via some command in the Startup-Sequence? If
you've got an auto-config board hooked up, the OS might just place it in an
area that conflicts with the resources of the CSA board. Unless a
memory-mapped item is auto-config, you can't expect it to work in conjunction
with any other peripheral, unless it sits somehow in Amiga reserved memory.
These are a few ideas you may be able to look into, perhaps someone else has
others. -Dave
The Comspec board is not buffered as far as I can tell. All pins on the 86 pin
female connector except the config pins are brought directly through the board
and soldered directly to the edge connector outboard.
Regards, Larry.
Paul,
I don't have experience, so the reason I am leaving this message is
because I am almost ready to by CSA board. I am trying to find anybody who has
worked with it and can tell me about andy SoftWare/HardWare compatability
problems and also tell me the low down as to whether it's worth the money (how
much faster is it?).
Any help you can offer is greatly appreciated.
Thanks
Todd Weiss
Triangle Business Systems