6 Nov
2017
6 Nov
'17
11:07 a.m.
william degnan writes:
On Sun, Nov 5, 2017 at 12:43 PM, Aaron Jackson via
cctech <
cctech at classiccmp.org> wrote:
The only thing I can think of with the terminator is that by using the
bulkhead connectors on the back you would end up with something like
this:
|--- logic board
pdp11 rl02 |
--------------------[]--+
|
terminator ---|
but I built my terminator directly onto the end of a ribbon cable, and I
realised that it is actually slightly different. More like this:
pdp11
----------------------------+---------+
| |
logic terminator
board
I wouldn't thought it would matter but maybe timing is very sensitive. I
can imagine something like this causing an issue with 10base2 networking
for example.
Thanks for the information.
Aaron.
Hi everyone,
I have managed to hook up an RL02 drive to my PDP-11 (thanks to Dave
Wade for the drives) . This took me longer than I thought it would - I
tried with a flat ribbon cable with a DIY terminator going straight into
board , but couldn't get it to work. Removed the terminator, and the
fault light turned off. So that's positive.
I tried to load a cartridge, which I had cleaned, inspected and
generally appears to be in good condition. It started to spin up and I
could hear it getting faster, but after 30-40 seconds the fault light
returns. I made a short video demonstrating this:
https://www.youtube.com/watch?v=japwBBodO8U
According to the manual the fault light can appear for the following
reasons:
- Drive select error... Surely this would come on at the start?
- Seek time out error... I'd have to hear the heads move first
- Write current in heads during sector time error... Same as above
- Loss of system clock... The fault light would be on from the start.
- Write protect error... I don't think it got that far
- Write data error... Same as above
- Spin error... Is this the only remaining fault?
So could the only cause be a spin error? I am wondering if the belt is
slipping or something like that?
Can anyone offer some advice?
Thanks,
Aaron.
At that point, for the time it takes the drive to be ready from a load
should be about 15 seconds. For you the Fault light comes on instead.
If I turn on my drives but leave the computer (11/40) off, the fault light
comes on immediately. If I then turn on the computer the fault light will
turn off, although I may have to press load first and if so it will turn
off after a few seconds. It's independent of the LOAD/READY lights
based on this informal comparison I'd venture you have a drive issue. I am
not 100% sure what your termination situation is. I have two drives, one
terminated but it's with a DEC terminator on the bottom port of drive 1.
The cable comes from the computer into drive 0. I have a cable going from
drive 0 port 1 to drive 1 port 1.
Bill