I have my aca500plus connected to a rev 5 motherboard. I have an amram-x 512kb expansion, and an 8372A Fat Agnus and decided to give upgrading to 1mb chip ram a try.
I have cut JP2 and soldered the top pads as per instructions on the net. According to what I'm reading all I should need to do now is turn the amram-x to "off" and it should be detected as chipram. However the aca500plus lists the ram as "unavailable" when I do this, when I turn it on and boot the Amiga it sees the ram as built-in (forget the exact term) and boots fine. I have _not_ cut the line near the trapdoor (EXRAM) because I from what I read the off/on switch on the Amram-x should take care of that.
However, I am having some issues with the upgrade as it seems that SysTest (crashing) and other utilities designed to check memory are finding errors. I was hoping to confirm the proper settings for this configuration so I can 100% rule out a configuration problem and move on to hardware troubleshooting. I am wondering what the various ram options should be set to? Currently they are (with the ram switch ON - because OFF == aca500plus doesn't see ram)
- $C0/Trapdoor RAM: disabled
- 7M Fast RAM: max
- 1M Chip RAM expansion: built-in
I read somewhere that I might need to make a modification related to the ROM (apparently EPROM based ROM chips require extra wiring), but I am not 100% sure what to do about this since my ROM is technically coming from the aca500plus.
Any help or insight you could provide would certainly be appreciated. Thank you!