Hello All, I have a technical question, hopefully someone has the answer/knowledge for this one.
I have this mobo (MB-8433UUD-A VER:2) and I'm running a custom BIOS (2014), I know someone posted it here (sorry I don't know your name, my compliments and gratitude to you!), so, everything seems to work fine, it's one of my favorite mobos, the only mod I did to it is install a socket for the RTC and a CR-32 battery, so I'm a happy camper on that side.
The problem:
I recently got a HardMPU (ISA) board (probably you all know about it) that simulates a MPU-401 to run my MT-32, the thing is, the motherboard is not sending a reset pulse on power-up and the HardMPU is not being initialized/recognized by the system unless I press the reset switch which do sends the reset pulse. I tested it in all my other mobos and they don't have this problem. Has anyone run into this? Any advise in what to look for? bad chips, etc? I traced the +5v "power good" line to the UM8886BF chip but don't know where to go from there, also traced it to the actual reset switch, there are some resistors and caps in between but they seem to be fine. There's a small chip (UM9515-01) that intrigues me that is mounted on a socket, don't know if it has anything to do with this and can't find any info about it. Anyway, I'm not an expert so I don't know anything about this chips.
Any ideas?
Thanks in advance!