RL01 termination pack pinout

From: Francis Bell <classiccmp_at_hexamon.org>
Date: Wed Aug 28 10:24:00 2002

Hmm,

Looking at this again, it appears that you're right about the
pinout of the resistor pack.

According to the FMPS the pinouts are as follows:

A gnd
B gnd
C dev sel 0 H
D drv sel 0 L
E drv sel 1 H
F drv sel 1 L
H write gate H
J write gate L
K gnd
L gnd
M sys clk H
N sys clk L
P gnd
R gnd
S write data H
T write data L
U gnd
V gnd
W drv command L
X drv command H
Y read data L
Z read data H
AA gnd
BB gnd
CC status in L
DD status in H
EE gnd
FF gnd
HH status clk L
JJ status clk H
KK gnd
LL gnd
MM drv sector pulse L
NN drv sector pulse H
PP drv ready L
RR drv ready H
SS drv err L
TT drv err H
UU AC LO in L (not as shown on RL02 FMPS, which says UU is gnd)
                UU is cut at the terminator
VV gnd

So I guess the active pins are seeing 82ohm to ground. I therefore
suggest you could build a much simpler version of the terminator by
connecting only the active pins to ground via 82ohm.

(The printsets for both the RL01 and RL02 drives do not agree with the
controller printset - both say that UU is gnd, whereas the controller
printset says this is AC LO in L - the controller printset appears
to be correct).

This terminator does work by the way - at least with my RL01.

Francis

----
Tony Duell wrote:
  >>Just to clarify, the following is the pinout of a terminator that works
  >>with an
  >>RL01 drive. It *should* work fine with an RL02 since the same interface
  >
  >
  > The same terminator is used with the RL01, RL02, RK06 and RK07 drives
  > (and it's the same no matter which controller you use too). I have never
  > heard of a terminator which works with the RL01 and not with the RL02,
  > and electrically such a thing would seem to be impossible.
  >
  >
  >>card works with both, so unless there's some oddity about the RL02, this
  >>should do the trick:
  >>
  >>Opening the pack, there is a single large resistor pack, 40 pin.
  >>Looking at the back of the resistor pack (i.e. looking at the outside of
  >>the RL01 drive connector)
  >>the pack is marked with pin numbers; pin1 is at the bottom right, pin 2
  >>is at the top right, pin 39 is at the bottom left
  >>and pin 40 is at the top left. Pin 39 has been cut. All other pins are
  >>connected.
  >>
  >>The resistor pack part number is 13-13242-00 SSM 7934
  >>
  >>Neither side appears to have commoned pins.
  >>
  >>Each opposing pair of pins has 160 ohm between them (i.e. between
  >>pins 1-2, 3-4, 5-6 etc.) Obviously 39-40 is open circuit.
  >
  >
  > I think you'll find it's rather more complicated than that. One of the
  > (corner) pins is a +5V supply from the drive (essentially TERMPWR). One
  > of the other (corner?) pins is ground. I believe each pin is
connected to
  > the tap on a potential divider between +5V and ground -- a similar
  > circuit to a passive SCSI terminator, or a Unibus terminator, or... but
  > with different value resistors.
  >
  > No manual that I have seen gives the resistor values, alas.
  >
  > -tony
  >
  >

Received on Wed Aug 28 2002 - 10:24:00 BST