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Short blocks of code for pdp-11s
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Short blocks of code for pdp-11 computers. They are stored as human-readable octal dumps. I use my serial11 program to upload them to a running pdp-11 over a serial line. All of these utilities live below address 010000, so that's a good place for the serial11 loader routine.


A library of useful utilities for various things.


A light chaser program for the pdp-11/45 that displays prime numbers.


Another library of useful utilities, this intended for the EMON monitor below.


An interactive serial monitor. Load coredump first, then this. Set the stack pointer R6 to 000770, and then start execution from 001200. The monitor expects a DL11 serial console at the usual address 177560.

The EMON monitor is set up with five commands:

  1. LIST, which lists the commands
  2. DUMP, which sends an octal dump of memory contents over to the serial console
  3. DEPO, which deposits octal words into memory. Press ENTER on a blank line to exit.
  4. STRG, which encodes an EMON standard string (first byte is the string length, followed by byte-packed ASCII characters) in a location you specify from text you type.
  5. VECT, which starts execution (as a subroutine call) to a specified address. To get back to the monitor, merely call
000207 RTS PC
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