Instruction Set

Registers:

• Single 12 bit Accumulator (AC) with 1 bit Link (Carry).
• 12 bit program counter.
• 3 bit data field and instruction field for addressing more than 4k.
• Extended arithmetic element (EAE) 12 bit MQ register and 5 bit step counter.

Instructions:

AND – AND memory with AC.

TAD – Two's complement add memory with AC.

ISZ – Increment and skip if zero.

DCA – Deposit to memory and clear AC.

JMS – Jump to subroutine.

JMP – Jump.

IOT – Input Output Transfer, control peripheral.

OPR – Bits control shifting, skipping, clearing, incrementing etc.

Notes:

Probably too much information to really learn. Intended to give a feel for instruction set.