I had an 11-23, and that had a monitor in the CPU (proper CISC!), writing to a serial port. That meant that I typed the boot loader into a terminal, and hence h

I had an 11-23, and that had a monitor in the CPU (proper CISC!), writing to a serial port. That meant that I typed the boot loader into a terminal, and hence had a pre-recorded sequence I replayed to the port to boot the machine.