IBM 5160 Motherboard - ROM information
BIOS ROM's
U44
BIOS ROM's
On the 5160 motherboard, there are two 32 KB sized BIOS ROM chips (of type 27256), one in socket U18 and the other in socket U19.
Additional information about that is at here.
Chip U44
Per the diagram at here, U44 is involved in RAM bank selection.
IBM's circuit diagram for the IBM 5160 motherboard has U44 indicated as being type 24S10, which is a 256 x 4-bit PROM of a particular pinout.
Based on the cross-reference at here, the 74S287 is one of a few alternatives to the 24S10.
U44 in a photo at here, is a TBP24S10N, stamped with the IBM part number of 5000084.
U44 on one of my IBM 5160 motherboards (of type 256-640KB), is an N82S129N, stamped with the IBM part number of 6359123.
Content of the chip: {yet to locate} (the MAME project has this as file 'xt u44 ibm.bin')
