Built a v0.2 version of the board and unfortunately it's still not working on my test boards. I'm observing the same behavior as the v0.1 board I built previously.
- The AMD test board is not detecting the bridge.
- Intel test boards refuse to boot unless I disconnect the TPM cable (whether dISAppointment is powered or not does not matter). I'm not testing the LDRQ there.
Also, in my case, -12V and -5V LEDs are not lit. I did make an inspection of the board after soldering and could not find any apparent issue with the related parts.
I put a debug card on the ISA slot. While not getting any POST code, the -12V LED on the card was lit, however.
I'm suspecting the 12V-ATX adapter I'm using to power the dISAppointment may not be working as intended. I'll be getting an ATX 24-pin splitter (so it gets power directly from my PSU) and test it again when I have time...
By the way, I wonder if there were ever any desktop motherboard model confirmed (at least per boardview) to have actually exposed the LDRQ pin on the TPM header.
NJRoadfan wrote on 2023-09-24, 03:54:
Regarding the presence of DMA on the LPC bus. There are STILL motherboards shipping with LPT headers (Intel H610 based!) that appear to support ECP mode, which requires the use of a DMA channel.
Interesting... but does ECP really work there? I wonder if there is still any actively used appliance that requires ECP.