MOP
嗨,老問題囉,51定址詳細觀念圖如下
| type | SDCC | instruction | size | addressing |
| (A) program | __code | MOVC | 64K | index direct |
| (B) external | __xdata | MOVX | 64K | indirect |
| (C) internal(80~FF) | __idata | MOV | 128 | indirect |
| (C) SFR(80~FF) | __sfr | MOV | 128 | direct |
| (C) internal(0~7F) | __data | MOV | 128 | direct/indirect |
| type | read | write | register |
| direct | MOV Rn,direct MOV direct,direct | MOV direct,Rn MOV direct,@DPTR MOV direct,#data | R0~R7,A |
| indirect | MOV direct,@Ri MOVX A,@DPTR | MOV @Ri,direct MOVX @DPTR,A MOV @Ri,#data | R0,R1,DPTR,A |
| index direct | MOV A,#30h MOV DPTR,#300H MOVC A,@A+DPTR | X | A,DPTR |
