ltning wrote on 2021-07-27, 15:08:

Hola, […]
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Hola,

I got a DC200 ISA IDE caching controller, and if installed the system (a 386) does not POST at all. However if I remove the firmware chips (even, odd, and X - three chips), the system POSTs fine, so it's not a purely electrical issue (I think). My current theory is that I need to flash new firmware chips for this one, but I'm lacking the actual firmware to do so..

Anyone with a DC200 able to dump their firmware and make it available somehow? 😀

I'll also take suggestions for other similar hardware (must be ISA) ..

/Eirik

Is there another onboard or slotted IDE controller in that setup ?

Sometimes its good to remove the rom chips.. And cleaning the IC socket underneath it with deoxit d5. And place the roms back.

I had a card where the rom didnt work.. But after cleaning it was working again.

So things are getting more interesting here.

When inserting the card as-is, POST fails as in *no video signal*, no beep, nothing. For all intents and purposes, completely dead.
The card seems to be a "museum piece"; it even came with a paper label on a thread. And the BIOS chips look like they're mounted the wrong way - the "hole" at the end of the chips were facing the opposite way of the corresponding "hole" in the sockets.
If I turn the chips around, I get a series of slow, varying pitch beeps (but no video). So either the chips have been permanently damaged by being inserted the wrong way before, or they're in the wrong way now. It's kinda hard to know. Removing the chips completely lets the system POST, but that's clearly not a workable situation.

I can also mention that the onboard 286 CPU does warm up a bit fairly soon after power has been applied. Not scolding hot or anything, but clearly it's being powered.

darry wrote on 2021-07-27, 16:45:

Is there another onboard or slotted IDE controller in that setup ?

No, I've removed that (and disabled the IDE controller on the GUS Extreme also installed.

Robin4 wrote on 2021-07-28, 00:55:

Sometimes its good to remove the rom chips.. And cleaning the IC socket underneath it with deoxit d5. And place the roms back.

Yeah, I have some contact/electronic cleaner (CRC) so I'll be trying that. But the mystery of the chip orientation remains.

/Eirik

if the bios chips were mounted the wrong way then they are dead. no point in trying them any further. they need to be replaced.

weedeewee wrote on 2021-07-28, 09:16:

if the bios chips were mounted the wrong way then they are dead. no point in trying them any further. they need to be replaced.

Even if it's EPROMS (not EE)? Anyway, that's why I'm asking if someone has a working card and can dump the ROMs..

/Eirik

yes, most chips don't like it when their ground gets 5V and their 5V gets grounded.

please make a photo of your card so we can see the situation you are now in.

Robin4 wrote on 2021-07-29, 22:09:

please make a photo of your card so we can see the situation you are now in.

Sorry for being late with this.
I took off the bracket for reasons unrelated to this project; it was in what I'd describe as pristine condition when I received it.

The chips definitely seems to have been inserted the wrong way though; when I got it they were the other way round from what you see in the attached picture. The ordering seems correct, though - based on other pictures I've found.

I've also tried with different RAM; both with and without parity.

/Eirik

as I already said, since you said the eproms were in the wrong way, they are now dead.
Turn'm into earrings, use'm to comb the fluf out of your dogs or cats hair, or leave'm pin side up on the floor for some unsuspecting person to walk on and rush'm to the doctor or hospital.
They're not of any use anymore besides decorative and a reminder of what not to do.

The circled wire has suffered too much current and destroyed itself.

To close off this thread with some good news: I got my hands on a DC200 with upgraded (LBA-enabled) firmware, EEPROM-images of which can be found here:
Re: Looking for LBA-BIOS of Promise SuperIDE DriveCache DC-200 ISA Cache Controller

I'm now happily using 8GB CF cards in my 386. Funny how the entire OS partition fits in the 16MB cache on the board.

It very likely does nothing for actual performance, but that's never been what this project has been about :)

/Eirik