DISTAR LDD-103 floppy drive PROM dump

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Glenn Anderson

Tinkerer
Sep 26, 2022
31
43
18
I have two DISTAR LDD-103 floppy drives, and I thought it might be useful to dump the PROMs from them. These are drives for the Apple II that have direct drive servo motors and track zero sensors, so are quite nice to use. The PROM is directly connected to some of the drive inputs, so is vulnerable to being damaged if the drive is incorrectly connected, as featured on Adrian's Digital Basement.

Also important is that one of the drives has an N82S123AN PROM, which has push-pull outputs, so RP1 is not populated on that drive. The other drive has a TBP18SA030N with RP1 populated.

The contents of the PROM are the same for both drives:
00: 53 C3 D3 C3 D3 53 D3 D3 D3 D3 53 D3 D3 D3 D3 53 10: 40 C3 86 83 CC 40 86 86 D9 99 40 83 8C 89 8C 40

DISTAR LDD_103 20 pin.jpeg


DISTAR LDD-103 D19.jpeg