Table of Content  Branch Up  

The Console

The Heritage/1 Console is very simple. It consists of two parts: The bottom half is designed for "programming", that is entering code into main memory. The upper half is designed to facilitate low level software and circuitry debugging.


The computer can operates in four different Operational Modes: RUN, SLOW, STEP and PROGRAMMING. It can also be Halt. The desired Operational Mode can be set from the OPERATIONAL MODE block. After power-on or reset, the computer is in Halt condition.

While in RUN mode, the computer operates at full speed. In SLOW mode, the system clock is replaced with a very slow one (several Hertz) which frequency can be adjusted using the rotary knob. When in STEP mode, the computers halts after the current instruction has finished execution; pressing the STEP button again causes the next instruction to be fetched and executed. When putted in PGM mode, the programmer block at the bottom can be used.

Bus content and different control signals are constantly monitored by LEDs no matter the current Operational Mode. The DATA and ADDRESS LEDs monitor the internal Address and Data buses respectively. Specially useful is the FAULT LED which lights to indicate a CPU exception condition. After a fault, the computer halts automatically.