Hi there
I have an IDE controller that I'm struggling to configure. It's a 486 build and I already have another controller that takes care of the IDE2SD and floppy drives.

As you can see from the pictures the cards is configured using a set of DIP switches using the following options
BIOS
MEM-0
MEM-1
IDE-B
IOS-0
IOS-1

There is nothing on the silk screen that would explain what BIOS setting does. I assume it's like an on/off switch for the controller itself. Perhaps, in ON position it will be detectable in BIOS, in OFF position it will be disabled.
MEM-0 and MEM-1 set memory addressing, IDE-B enables or disables Secondary IDE channel. IOS-0 and IOS-1 set IO space / IRQ.

I tired few different combinations of settings, but whatever I do must be causing a conflict with the main controller or ether devices as no drives are being picked up in BIOS, including ones that are connected to the main UMC controller.

Also I assume that switch in up position equals OFF and down equals ON.

I'd appreciate some input especially when it comes to memory addressing. I guess any free IRQ and I/O will be fine as long as it does not conflict with existing devices.

UPDATE:

I think I know what the problem might be. I have the impression that this board only supports one IDE channel, regardless of IDE controller used.

There are no references in BIOS to Secondary IDE channel, only Primary. Also during POST two drivers are listed - Primary Master and Primary Slave.

Is this common in 486 boards? Is there a way around it?

My predicament is that I use SD2IDE adapter and would like to use a CDROM as well, but they don't want to play ball if both are on the same ribbon cable.