P2 Assembly Instruction Size
expElec
Posts: 27
I'm probably not seeing something obvious, but I've been getting familiar with the Assembly Manual and am looking at the COGINIT instruction.
The manual says the instruction is 7 bits, D is 6 bits, and it uses the lower 20 LSBs of S. If my math is correct that makes 33 bits. How does that fit into a 32 bit memory location?
Comments
The format of Dest is %E_N_xVVV.
Maybe that do-not-care bit gets ignored when assembled?
You're mixing up the size of the instruction vs the size of the data it uses. D and S are always 9 bits and are either a register number or a 9 bit immediate. The immediate encoding can be extended to 32 bits using an AUGS/AUGD prefix.
Ah, got it. Thanks.