The only DIP-28 EEPROMs I have in my bitnare 32 Kbyte, which are supported XTIDE BIOS. I grabbed ide_386l.bin from their website and programmed a Winbond W27E257-12 EEPROM in an external programmer. I plugged the EEPROM into the DIP-28 socket on the Intel EtherExpress Pro100 ISA LAN adapter card. There was no notch on the DIP socket to indicate orientation, so I looked for GND and VCC on the socket using a DMM. Pins 14 and 15 measure to be GND, however the datasheet shows Pin14 as GND and Pin 15 as Q3, which is a data input/output. Hmm... Also, Pin 28, which is supposed to be Vcc, has only 28 ohms of resistance before heading to the 5V rail. Hmm...
Nonetheless, I turned the computer on. Screens stayed blank. I put my finger on the EEPROM and my skin was burned. There's a small welt on my finger now (24 hours after the burn). It was VERY hot, as if I put my finger on my wood stove's glass door. I turned the system off and removed the EEPROM. System still works.
Were there non-standard pinouts on these Intel/IBM ethernet adapters? Or did I need to have blanked the EEPROM before I could turn on the system?
According to the XTIDE website, I am supposed to program the EEPROM while in the computer, but I didn't think I'd get a short if I didn't.
All BIOS binaries available here must be properly configured with the configuration tool XTIDECFG.COM before flashing/programming to ROM. In addition to configuring the BIOS file for use with your specific hardware you must also make sure the file is checksummed by saving the file to disk as that will create the padding and checksum required for installation in a computer.
I am reluctant to try it again with the EEPROM blanked. Should I? Also, it doesn't appear as if the boot ROM can be enabled by force. The DOS setup utility needs to detect the presence of a boot ROM before the option gets un-greyed. See here:
Where to go from here? Is there an ISA card that just hosts the EEPROM for the purpose of XTIDE BIOS for use with my motherboard's onboard IDE controller?
I couldn't find a list of supported hardware to ensure that XTIDE BIOS will even work with my onboard IDE controller, which I think is in the southbridge, UM8886BF.