First, are you using the provided setyp and or soundset/soundsetup programs supplied with the games? Also, does the other computer which the card works fine in its isa slot, does it have any drivers or extra autoexec.bat and config.sys lines added to configure the card? What games have you tried?

No I'm operate in slightly lower level than setup.exe or other progs. Just writing bits in Gus control registers and seehow Gus codec behaves. I suspect that it's a hardware problem, cause iochrdy signal level differs from mb with soldered bridge chip and external bridge card

Hmm, possibly a faulty and or dirty ISA slot. In the system that it is not working properly, does it have an add-in isa riser card?

The GUS does require 16 bit IO writes compared to the soundblaster only needing 8BIt ones. Could this cause problems?

anthony wrote:

No I'm operate in slightly lower level than setup.exe or other progs. Just writing bits in Gus control registers and seehow Gus codec behaves. I suspect that it's a hardware problem, cause iochrdy signal level differs from mb with soldered bridge chip and external bridge card

IOCHRDY is controlled by the card, not by the motherboard. It's used by peripherals to force the system to extend the bus cycle (aka, the card pulls it 'low' while it's not ready to send/receive data). Can you elaborate on 'signal level differs'?

The GUS does require 16 bit IO writes compared to the soundblaster only needing 8BIt ones. Could this cause problems?

How should I check it?

Maeslin wrote:

IOCHRDY is controlled by the card, not by the motherboard. It's used by peripherals to force the system to extend the bus cycle (aka, the card pulls it 'low' while it's not ready to send/receive data). Can you elaborate on 'signal level differs'?

Iochrdy high level on my external bridge card was 2.2v oppesed to 5v on other motherboards. At now I solved this issue but Gus still not respond to commands. Ultrinit.exe shows that no 16 bit recording facilities found

Here is how it looks:

On mb I disconnect idsel on 8888 from ad22 and connect it to idsel on 8888 on bridge card, so bios operates with external 8888 like it onboard chip. I believe that bios program registers absolutely correctly and there is some sort of hardware incompatibility exists

P.s.

If I plug Gus to motherboard isa slot it operates successfully

Then it must be a problem with the add-in card. When installing the card, which irq slots does it fill?

anthony wrote:

Iochrdy high level on my external bridge card was 2.2v oppesed to 5v on other motherboards. At now I solved this issue but Gus still not respond to commands. Ultrinit.exe shows that no 16 bit recording facilities found

... 2.2V? Possibly a bad solder joint. That level really shouldn't happen what with TTL logic. Either the card is trying to pull it low but doesn't have quite enough drive or the bridge chip has too strong a drive on that pin compared to what it's supposed to be.

IOCHRDY is pin A10; 10th pin on the 'component' side of the ISA card starting from the bracket. Try to trace it and see if there's anything funky going on on either the adapter card or the sound card.

dosquest wrote:

Then it must be a problem with the add-in card. When installing the card, which irq slots does it fill?

Bridge card by itself doesn't takes any Irq or dma

Maeslin wrote:

... 2.2V? Possibly a bad solder joint. That level really shouldn't happen what with TTL logic. Either the card is trying to pull it low but doesn't have quite enough drive or the bridge chip has too strong a drive on that pin compared to what it's supposed to be.

IOCHRDY is pin A10; 10th pin on the 'component' side of the ISA card starting from the bracket. Try to trace it and see if there's anything funky going on on either the adapter card or the sound card.

At this time signal level at a10 is 5v how it should be. I solved this issue, but still no luck with gus