Memory mapping and PCMCIA

[alexh]

It really depends on the make / model of RAM card as to whether you can use more than 4Mbytes without screwing up the PCMCIA port.

The PCMCIA is mapped to the upper 4Mbytes of the traditional 8Mbyte FAST-RAM area.

If you have 8Mbytes of contiguous RAM in standard 24-bit fast RAM area then you WILL overlap the PCMCIA address and get problems.

Some cards get around this by adding the other 4Mbytes of RAM to other strange address locations. They sometimes need an extra driver to activate the other 4Mbytes.

[alexh]

rkauer wrote:
Most of them have a way or another to bypass the PCMCIA RAM adress issue.

I have 128 Mb 60ns FastPage SIMM(yessssssss!:evilgrin:) on mine MX 1230 XA (Microbotics).

That is an accelerator. Almost all accelerators can be PCMCIA friendly as they can put FAST RAM in 32-bit address space.

The conversation is about RAM cards.

[alexh]

Zipper wrote:
Except with those crippled cheap accelerators with 24bit addressing.

Note that I said "almost all".

Hodgkinson wrote:
I’m trying to set up PCx on the system

Why would you EVER want to do that? FFS use a PC! You've lost all my sympathy :-)

Long since gone are the bad old days when all we had was an Amiga.

[alexh]

http://aminet.net/search?query=priority+memory

[alexh]

http://en.wikipedia.org/wiki/ARexx