booting os/8

Jerry Weiss jsw at
Tue Mar 21 23:33:46 CDT 2017

> On Mar 21, 2017, at 10:49 PM, W2HX via cctalk <cctalk at> wrote:
> Hi folks,
> I have a PDP-8/e that I've been working on. I have completed construction of AK6DN's RX01/02 emulator. I got to the step tonight where I was trying to boot an OS/8 disk image and nothing was happening. I realized that I do not have the bootstrap diode board in my 8/e so begin the bootstrap triggered by the "SW" switch.
> Does anyone have the program I can toggle in for the bootloader? What I found is somewhat confusing. Here is a discussion on this topic.
> It seems one fellow was attempting to edit/improve the bootloader of another fellow. I was wondering if anyone has distilled this into something simple. At the moment, I care only about booting from RX01-Disk0.
> Any pointers greatly appreciated. Thanks
> Eugene W2HX
The Data Systems Design DSD 440 Disk Drive Manual on page 5-34 has a PDP8 RX01 drive 0 Bootstrap.    I can’t vouch for it personally.

The listing basically consists of

	• Load the following bootstrap sequence through the front panel.,

33/ 6755 
34/ 5054 
35/ 5045
45/ 7326 
46/ 6751
47/ 4053
50/ 3002
51/ 2050
52/ 5047
53/ 6753
54/ 6753
55/ 5033
56/ 6752
57/ 5453
60/ 7004

	• Start at location 33. IF the diskette is write-protected, the computer will halt at location 7604. Pressing the CONTINUE (or run) switch on the front panel will then start the monitor. Additionally, if at any time the is halted and you wish  to restart in the monitor, this can be done by the diagnostic diskette in drive 0 and restarting at location 7605. 

Note: The halt/restart locations applies to a vendor supplied diagnostic.  

Good luck,
Jerry  WB9MRI

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