I received my "Omnibus to USB" board for my PDP-8/E a while back, but a
heavy work load prevented me from trying it out until the last couple
of days.
Review of the "Omnibus to USB" board by Philipp Hachtmann:
----------------------------------------------------------
What it is:
A KL8E compatible board which runs at a "blinding" transfer
speed. Currently, it's primary use is to dump and restore RK05 packs on
a PDP-8/E/F/M to/from a PC.
Speed: Transferring an entire RK05 pack to a PC takes less than 51
seconds. With verify it takes 1 minute and 40 seconds. Restoring a pack
from a PC image with or without verify to the RK05
takes the same amount
of time as dumping.
Will it work O.K. on a "loaded" system?:
In short, the answer is "yes". Here's the configuration of my test
PDP-8/E:
(1) KK8-E CPU
(1) KE8-E Extended arithmetic element
(1) KM8-E Memory extension and timeshare
(4) 8KW DEC Memory - total 32KW
(1) RK05 Disk Drive
(1) VC8/E X/Y -> VT01
(1) RX8-E Interface -> RX02
(1) MI8-EP Hardware bootstrap loader for RX01/RX02
(1) KL8E Async
(1) DK8-EC Crystal Real Time Clock
(1) Omnibus to USB
This system is at the max in terms of current draw for the H724 power
supply.
How difficult is it to use?
It's very easy to use. It comes pre-configured to use I/O addresses 40
and 41. (Switch changeable). All the software below is downloadable
from Philipp's website.
To dump an RK05 pack here's the procedure:
Load the SPEED8.RIM program into the PDP-8/E using the standard RIM
loader. (Or use SPEED8.BIN via the standard OS/8 loader). Halt the
system and set the switch register to 200. Clear/Load/Run
On a PC running Linux, run "rktool" as follows:
To dump an RK05 disk with verify: rktool -r -V filename
To restore and RK05 disk with verify: rktool -w -V filename
You can dump/restore as many packs as you like as long as you leave
SPEED8 running in your 8/E/F/M.
Is there anything to watch out for?
1) It's important to set your Linux USB port properly with the
following:
"stty -F /dev/ttyUSBx raw -echo"
2) There's a minor glitch in the current version of rktools. If you
don't ask for a verify, you will get a large negative number of verify
errors indicated at the completion of the job. This is a false
indication - the image is perfect. My solution is to always verify
(-V). The board is so fast that there's no reason not to verify.
Regards,
Lyle
--
Bickley Consulting West Inc.
http://bickleywest.com
"Black holes are where God is dividing by zero"