Dec RQDX: What kind of chips on it?

Mattis Lind mattislind at
Tue Jan 5 11:32:42 CST 2021

I used the Davids MFM emulator to emulate an RQDX2 formatted disk a few
years ago. I tested both with a RQDX1 and RQDX2. Both were tested with
10.0D firmware. I know that we had some initial problems which David fixed
quickly. As far as I remember I did read disks as well. But I have no
traces of these read disks since the flash of the Beaglebone got erased.

One thing to keep in mind with RQDX1 and RQDX2 is that they are not format
compatible among certain versions. Maybe the firmware that wrote the disk
is older and thus it cannot be read by the mfm emulator since it was
adapted to 10.0D?


Den mån 4 jan. 2021 kl 23:40 skrev Chris Zach via cctalk <
cctalk at>:

> Can someone check to see if a RQDX2 used the Western Digital chips to
> interface to MFM drives? Reason I'm asking is the MFM emulator can
> identify an RQDX3, and also a Pro/350 controller but this particular
> RD52 I have (which was verified by me to run Digital Mumps) is reading as:
> root at beaglebone:~/mfm# ./mfm_read -a
> Board revision C detected
> Found drive at select 3
> Returning to track 0
> Drive RPM 3525.4
> Matches count 36 for controller WD_1006
> Header CRC: Polynomial 0x1021 length 16 initial value 0xffff
> Sector length 512
> Data CRC: Polynomial 0x1021 length 16 initial value 0xffff
> Interleave mismatch previous entry 0, 9 was 1 now 0
> Selected head 8 found 0, last good head found 7
> Read errors trying to determine sector numbering, results may be in error
> Number of heads 8 number of sectors 18 first sector 0
> Unable to determine interleave. Interleave value is not required
> Drive supports buffered seeks (ST412)
> Disk has recalibrated to track 0
> Stopping end of disk search due to recalibration
> Number of cylinders 512, 37.7 MB
> Thanks!
> CZ

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