git.joshuawise.com / fpgaboy.git / blame
| Commit | Line | Data |
|---|---|---|
| e7fe9dc2 JW |
1 | `define INSN_POP_reg 9'b011xx0001 |
| 2 | ||
| 81358c71 JW |
3 | `ifdef EXECUTE |
| 4 | `INSN_POP_reg: begin /* POP is 12 cycles! */ | |
| 5 | case (cycle) | |
| 5c33c5c0 JW |
6 | 0: `EXEC_READ(`_SP) |
| 7 | 1: `EXEC_READ(`_SP + 1) | |
| 81358c71 | 8 | 2: begin |
| 5c33c5c0 JW |
9 | `EXEC_NEWCYCLE |
| 10 | `EXEC_INC_PC | |
| 81358c71 JW |
11 | end |
| 12 | endcase | |
| 13 | end | |
| 14 | `endif | |
| 15 | ||
| 16 | `ifdef WRITEBACK | |
| 17 | `INSN_POP_reg: begin /* POP is 12 cycles! */ | |
| 18 | case (cycle) | |
| 19 | 0: begin end | |
| 20 | 1: begin | |
| 21 | case (opcode[5:4]) | |
| 5c33c5c0 JW |
22 | `INSN_stack_AF: `_F <= rdata; |
| 23 | `INSN_stack_BC: `_C <= rdata; | |
| 24 | `INSN_stack_DE: `_E <= rdata; | |
| 25 | `INSN_stack_HL: `_L <= rdata; | |
| 81358c71 JW |
26 | endcase |
| 27 | end | |
| 28 | 2: begin | |
| 29 | case (opcode[5:4]) | |
| 5c33c5c0 JW |
30 | `INSN_stack_AF: `_A <= rdata; |
| 31 | `INSN_stack_BC: `_B <= rdata; | |
| 32 | `INSN_stack_DE: `_D <= rdata; | |
| 33 | `INSN_stack_HL: `_H <= rdata; | |
| 81358c71 | 34 | endcase |
| 5c33c5c0 | 35 | `_SP <= `_SP + 2; |
| 81358c71 JW |
36 | end |
| 37 | endcase | |
| 38 | end | |
| 39 | `endif |