MAMEWorld Forums - EmuChat - Re: Delicious Amiga Arcadia system for sale in Sweden

This is my guess:

ROM_LOAD16_BYTE_BIOS( 3, "gcp-1-hi", 0x000000, 0x10000, CRC(67d44523) - U16
ROM_LOAD16_BYTE_BIOS( 3, "gcp-1-lo", 0x000001, 0x10000, CRC(65d9b9cf) - U11
ROM_LOAD16_BYTE_BIOS( 3, "gcp-2-hi", 0x020000, 0x10000, CRC(1d7594ae) - U17
ROM_LOAD16_BYTE_BIOS( 3, "gcp-2-lo", 0x020001, 0x10000, CRC(e776198d) - U12
ROM_LOAD16_BYTE_BIOS( 3, "gcp-3-hi", 0x040000, 0x10000, CRC(3e7364be) - U18
ROM_LOAD16_BYTE_BIOS( 3, "gcp-3-lo", 0x040001, 0x10000, CRC(87229e0d) - U13

Why be contrary?

Because I am familiar with PCB layout software. The "U" designations are always near the notched side of the ICs so the parts stuffers have a reference to keep from putting the IC in backwards. (Yes, years ago, actual humans stuffed PC boards with components - not robots)

The PCB printed tags for U11, U12, & U13 are not visible due to the angle of the shot. (Well, the top half of the lettering is, but it's hard to see it due to the glare from the flash) So why do I think they are numbered that way? - there is a U10 visible below what I think is U11, and there is a U14 visible above what I think is U13.

I think U23 and U24 belong to the unpopulated ICs and U25 belongs to the SRM2064C.

In this orientation view, the ICs are numbered from left to right, bottom to top.

So I think the hidden-from-view/poor visibility IC tags follow this pattern.

Of course a better shot would be actual proof, but if that is not possible, I think the IC numbers I guessed are the best representation.