Make sure they don't get killed by the power supply.

Every C64 power supply I've ever had, with the exception of the upgrade ones that go with the REU, have lost their 5V regulation, and done major damage to the host computer, with the exception of the ones which I caught before plugging them in.

Hi everyone,
i have a working FDC interface for 1.44MB diskette, look at this project: http://65xx.unet.bz/

I used a chip found in some old PC-XT old FDC boards: the UM8388, clocked at 24MHz, able to handle 500Kb/s rate (1.44MB) or 250KB/s (720 Kb).
In my project i used a DMA chip (82C37) but is not mandatory: the 8388 can be programmed both in DMA mode/not-DMA mode. In the last case the time between 2 consecutive fetch of data from FDC should be not greater than 12uS, otherwise a loss of data happen (i interfaced the UM8388 with a 65816 clocked at 4MHz without problems).
In the past i tried some tests with the WD1772 clocked at 16MHz (but take care: WD1772 datasheet say clock should be at max. 8MHz), and worked fine for format/read/write 1.44MB diskette.
Programming UM8388 is very easy because have commands for format tracks, read/write multiple sectors. calibration of track 0, while WD1772 need more effort (both need a double-step calibration for format 80 trcks diskettes).

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