Bringing up a PDP-8e

Pontus Pihlgren pontus at Update.UU.SE
Mon Nov 28 02:26:34 CST 2016

On Sun, Nov 27, 2016 at 11:46:46AM -0800, W2HX wrote:
> Hi folks,
> This is my first vintage computing project. I have a PDP-8/e with the 
> following boards in this order.

Nice machine. Strange that you are missing a serial interface.

> Each core pair is 16KW. There are a bunch of other non-DEC boards 
> (ECRM) that I have removed for the time being.  You will notice that I 
> have no serial board (yet. I have a line on one).

What are those boards?

> Next, I will put the boards back in and start testing. I am looking 
> for some very simple programs that I can key in from the front panel 
> to do some basic testing. I have found simple programs on the internet 
> but they are all in assembler and I don't yet have the knowledge/tools 
> to convert them to switch-enterable programs. For example, here are 
> some good test programs but not directly enterable on the front panel 
> (or at least I don't know how). 

On the same site you will find palbart which is really handy for 
assembling programs from source.

But if you look at the testprogs, you have all you need, for instance:

The second column is memory address and the third column is the 
instruction, both values is in octal.

So, first set the switch register to 0000, which is all switches _down_. 
The press "LOAD ADDR" and next enter 2020, which is switch 1 and 7 up, 
all other down. Then press DEP. Notice the address should increment with 
one. Then deposit 5000, 7200 and so on from the list of instructions.

Finally set the SR to 0000, press LOAD ADDR, CLEAR and CONT. If all 
works you should have a running program that blinks the lights in some 

Here is some more details on how to use the console:

Good luck,

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