EXR
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| EXR | |
|---|---|
| Description | Execute register |
| Format | EXR <sr> |
| Code | 140 6008 |
| Affected | IR, and according to specified instruction |
| Type | User |
| Architecture | ND-100, ND-110 |
EXR is an assembly instruction. The contents of the register specified in the sr field (bits 3-5 of the instruction) is transferred to the instruction register and then executed as an instruction.
If sr contains a memory reference instruction with P-relative addressing, the address will be relative to the value of the P register for the EXR instruction. If sr contains a JPL instruction, the L register will point to the instruction after the EXR instruction.
It is illegal to use EXR <sr> to fetch another EXR <sr> instruction. Attempting this will set the error flag Z in the status register.
References
- Norsk Data Document ND–06.014.02 ND-100 REFERENCE MANUAL Page 3-46
- Norsk Data Document ND–06.029.01 ND-110 Instruction Set Page 45