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ISA 16 bit Memory Card - Help!

pauls640 said:
Thank you all. To make things simple, I installed the board on my 286 box going restoration. It has 1MB onboard, makin 640 base + 384k extended (machine counts this at boot).

Following these instructions,

http://www.minuszerodegrees.net/5170/cards/5170_memory_board_512K_2048K_switches.htm

I configured the dipsw to 1mb, so 'on on on off on', but ram is not seen at boot. The MoBo(wd286-wdm20) has a Phoenix BIOS, that lets you specify manually the amount of RAM, so I set 640k base + 2432K Ext.

When machine boots with PC-Dos, only the first 384k are recognized by himem.sys, whereas xma2ems.sys still says it cant find adapter... but Msd reports correctly 2432k of ext memory, probably because it just reads it from bios...

Do you think my dipsw configuration is wrong?
Click to expand...

This is not XMA memory, and 2432K extended memory total is wrong, because the card is set at 1MB starting address. It should be 2048k extended memory total. Since the card only allow the address to be set at 512K boundaries, the 1MB starting address is your best option.
 
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Ok, I fixed my errors in sizing matters (thanks stone and yuhong), here's where we stand: the pc boots normally with only onboard ram (640k+384k), the ram card is not seen at boot. Himem.sys only loads the 384k, nothing else. :(

Assuming no driver is required for the system to detect the card (as Ray says), I think the card might be faulty :(

I'll try to test some components on the card, there are only a couple capacitors and resistors, the rest is IC's.

What could I do as a last resort? Maybe reseating some ram chips? Or populate half or less ram on the card?
 
As yuhong pointed out, your IBM RAM card can only start at an address that is a multiple of 512 KB. So, you will need to disable the 384 KB of extended memory that you have, configure the IBM RAM card to start at 1 MB (the start of extended memory space), and then 'inform' your BIOS that the machine has 2 MB of extended RAM fitted.

My view is that with the BIOS and RAM card suitably configured, at power on, your 286 should be counting up to the total amount of RAM (motherboard + RAM card). If it is not, then there is no point in going any farther (e.g. loading a memory manager for the extended memory).
 
modem7 said:
As yuhong pointed out, your IBM RAM card can only start at an address that is a multiple of 512 KB. So, you will need to disable the 384 KB of extended memory that you have, configure the IBM RAM card to start at 1 MB (the start of extended memory space), and then 'inform' your BIOS that the machine has 2 MB of extended RAM fitted.

My view is that with the BIOS and RAM card suitably configured, at power on, your 286 should be counting up to the total amount of RAM (motherboard + RAM card). If it is not, then there is no point in going any farther (e.g. loading a memory manager for the extended memory).
Click to expand...

I'm sorry for this question, but I'm no expert: how do I disable the onboard 384k? The bios has no such option: only the amount of ext memory, plus shadowing and memory remap.

Thanks,

Paul
 
pauls640 said:
how do I disable the onboard 384k?
Click to expand...
You indicated earlier that the 384k appears as extended memory. If it is in fact appearing as extended memory, the question is instead, "How do I stop the 384K appearing as extended memory."

pauls640 said:
The bios has no such option: only the amount of ext memory, plus shadowing and memory remap.
Click to expand...
Whilst there are some generalisations, each BIOS does things in its own way. You'll have to experiment.

'Memory remap' sounds like a likely candidate.

With all of 384K presently appearing as extended memory, the BIOS doesn't have any memory available for shadowing. Maybe once you turn on BIOS shadowing, the BIOS will use all of the 384K for itself (rather than reducing extended memory by the amount of shadow RAM).
 
I have that WD board -- it was my first computer. Turn off memory remapping into extended and enable shadowing. Then the board will only have 640k available.
 
I understand: we allocate this memory as shadow AND turn off the remap to extended, so there is no memory hole, and the onboard and card memory don't overlap.

Thank guys, let's see what happens.
 
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