11 10 09 08 07 06 05 04 03 02 01 00
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| | | | | | | | | | | | |
|__|__|__|__|__|__|__|__|__|__|__|__|
| | |
| Opcode | Extension |
| | |
| 6-bit F | 6-bit E |
A is circularly shifted one place left.
A is circularly shifted two places left. This instruction is present only in serial number 37 and above.
A is circularly shifted three places left.
A is circularly shifted 6 places left. This instruction is present only in serial number 37 and above.
A is multiplied by 10. This is a microcoded combination of shifting left one and three times. It is apparent that, in the original design, there was a hope that this group of instructions could be expanded to multiplication by other small constants, where the constant would appear as the literal in the E field.
A is multiplied by 100. This instruction is present only in serial number 37 and above. Here, we see the abandonment of the plan inferred from the original instruction coding.
The error and halt instructions operate identically. The CPU stops and can only be restarted from the console by pressing the RUN switch.
This instruction was present in serial number 37 and above. Prior to this, the CDC 160 had no procedure call instruction. With the addition of this instruction, procedure calls with linkage through the accumulator could be done with a two instruction sequence.