Sender: sartaj AT cair DOT res DOT in
Message-ID: <394BA394.E2C616DE@cair.res.in>
Date: Sat, 17 Jun 2000 11:13:08 -0500
From: Sartaj Singh <sartaj AT cair DOT res DOT in>
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To: djgpp AT delorie DOT com
Subject: Memory access on custom ISA card
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Reply-To: djgpp AT delorie DOT com

We have designed an 8-bit ISA card with 64K of on-board memory. This
memory is mapped to 0xD0000 base address. In BorlandC 3.1 we are able to
access the memory by using pokeb and peekb instructions.

Recently we switched over to DJGPP because we found it far more
attractive and easy to work with as compared to BorlandC 3.1. However we
are stuck with trying to access this memory on our board. We have
already tried the following methods without success :

1. Using _farpeekb and _farpokeb with _dos_ds
2. Using _dosmemgetb and _dosmemputb
3. Using the _my_ds() descriptor

In order to ensure the proper functioning of DJGPP, we followed the
examples for accessing the video buffer (at 0xA0000, 0xB8000) which work
perfectly.

Pl suggest how we could access 8-bit memory boards sitting on the
ISA bus from DJGPP.

Thanx.