Do nothing. Do nothing. Do nothing. Stop.

So if I wanted to best describe the first program that ran on my DEC PDP-11/53 ... then it would have to be:

"Do nothing.  Do nothing.  Do nothing.  Stop."

But at least it worked.  I entered those commands as machine instructions in ODT (Octal Debugging Technique) and it ran.  Not much of a "Hello World" program though is it?

Here are the details of the instructions:

001000/240<lf>  ; NOP
001002/240<lf>  ; NOP
001004/240<lf>  ; NOP
R6/1000<cr>  ; set to start code at 1000
R7/1000<cr>  ; set PC to start address so we can use P and not clr PS
RS/340<cr>  ; set PS to disable interrupts
P<cr>  ; start program

That program was a hacked version of something I found here.  Now I need to make it do something better.

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