The MicroStepper operates by pulling the Z80 WAIT signal low whenever a READ or WRITE signal is detected.
When the computer operation stops it can be Reading or Writing and either to Memory or to a Port.
current address and data are displayed on the 6 TIL311 Hex displays.
The current state of MREQ IORQ READ and WRITE is displayed by 4 LED's
computer will stop until a flip-flop is operated – either by a push
button or by the slow pulsing 2Hz clock.
Front Panel Switches
GO Push Button – This controls the Single Step process when SW2
is switched to the STEP position.
3-Pole switch – (1) BREAK, when the switch is in this position
the computer can be run to any address. After setting the required
address on the thumbwheels press GO to run to the address. The computer
will halt and can be single stepped from this address when SW2 is
switched to (2) the STEP position.
switched to (3) RUN, the computer will run normally after GO has been
2Hz switch is used to run the computer very slowly, this enables any
sequence of instructions to be easily monitored.