16 Aug
2013
16 Aug
'13
4:31 p.m.
The actual data to/from the drive is almost raw;
there's just a
bitstream (at TTL level) from the controller to the drive to write,
and from the drive to the controller to read. So, other than
This sort of interface was quite common on hard disk units at that time.
SMD, for example has high-ish level seek, select, etc lines but raw data
to/from the head amplifiers. So do most DEC drives (RK05, RLs,
RK06/07,etc).
amplification and bit-shaping there is no processing
in the drive (no
de-serialization); there is a fair bit of electronics in the drive for
seeking and head selection, though.
What does your interface look like? The CDD (cartridge disk drive)
controller in the P850 has a 74 pin card edge connector. Does your
Do you mean P850 here. Philips had at least 3 series of I/O cards for the
P800 machines. The P850/855/860 took boards about A4-paper sized (a bit
larger) with connectors on the short edtes. These conenctors were
separate plugs soldered to the PCB with contacts like PCB edge fingers.
Connectros at one end fo th board go into the system bus, those at the
other end takje the peripheral cables
The P852/856/857/858/859 (I think) took boards with the connectrs on the
long edge. IIRC (and I have never seen such a mahcine 'in the flesh'),
the top and bottom conenctors conencted to the bus, the middle conenctor
was for the peripheral
The P851/P854 (and P853???) used double-height eurocards. The top
DIN41612 plug is the system bus, the bottom one is interurpts/DMA/etc.
The peripheral cables connect to conenctors on the front edge of the board.
My P854 has a controller for the X1215 disk drive in it. Alas I didn't
get the drive. This is a double-height Euroccard with, amongst other
thigns, an 8X305 microprocessor on it. The drive cable conencts to a 50
pin (IIRC) header on the front of this board, the oterh end of the cable
has a plug somewht similar to those used for the V.35 interface (although
with more pins).
Unfortuanately I don't have any useful documentation on this controller.
-tony