This page describes the following instruction:
- Group: PAIR
- Mnemonic: sa
- Opcode: 233d, E9h
- Encoding: 1_110_1001b (PAIR_SRC_DST)
- Pseudo-code: if (o+sir)>255 then d+=1; pc++
- S:SERIAL A:ADD
- Source is the Serial Input register (SIR).
- Add source to O. If this produces a carry bit, add the carry bit to D.
The 'S' source is a deserialised byte received over the serial bus. See Device Communication for how this works. The 'A' destination takes the source value as the addend which is added to the Data pointer (register pair D:O). See In-Page Branching for more on this.