I spent half an hour doing more cleaning of the crashed disk head and the results are looking quite promising. By comparison, look at the smudge on the non-crashed head from the lower surface of the removable pack. Not a mark on the disk surface and a bit of this tarry streaking which I have removed now.
|Good head with a bit of tar smearing|
|Crashed head after more cleaning|
|Bit of tar still in pole gap, otherwise looking pretty good|
SAC INTERFACE FOR ADDING PERIPHERALS TO THE 1130
I set up the slave FPGA to produce an ever varying set of signals on the 104 data lines carried on the fast SPI link between it and the master FPGA in the SAC Interface Box. This way, I can be sure that
CRC and Hamming SEC-DED logic is properly validating the link data.