Does DEC, for example with the RQDX3, only accept the
RD5{0..4}
_geometries_ with this controller or can there be others. Could a larger
drive be used in a "waste some tracks" mode with the RQDX3? This all
assumes a seperate formatter, mv2000 or XXDDP.
Somewhere I have a set of the sources for the RQDX1/2 boards. They
were designed to recognize certain disks from certain vendors. The
code does not make much attempt to truly determine geometry, it
uses hard-wired values, which is why only certain ones work.
I have no doubt that when the RQDX3 was done it was implemented in
the same way... that only certain disks from certain vendors would
be recognized. To have it recognize another disk, you would have
to add an entry to the disk characteristics table in the source
for the firmware and blast a new set of ROMs.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | email: gentry at
zk3.dec.com (work) |
| Unix Support Engineering Group | mbg at
world.std.com (home) |
| Hewlett Packard | (s/ at /@/) |
| 110 Spitbrook Rd. ZK03-2/T43 | URL:
http://world.std.com/~mbg/ |
| Nashua, NH 03062 | "pdp-11 programmer - some assembler |
| (603) 884 1055 (DEC '77-'98) | required." - mbg KB1FCA |
+--------------------------------+-------------------------------------+