git.joshuawise.com / fpgaboy.git / blame
| Commit | Line | Data |
|---|---|---|
| e7fe9dc2 JW |
1 | `define INSN_ALU_EXT 9'b100xxxxxx |
| 2 | ||
| c279b666 JW |
3 | `ifdef EXECUTE |
| 4 | `INSN_ALU_EXT: begin | |
| 5 | if ((opcode[2:0] == `INSN_reg_dHL) && (cycle == 0)) | |
| 6 | `EXEC_READ(`_HL) | |
| 7 | else begin | |
| 8 | `EXEC_INC_PC | |
| 9 | case (opcode[2:0]) | |
| 10 | `INSN_reg_A: tmp <= `_A; | |
| 11 | `INSN_reg_B: tmp <= `_B; | |
| 12 | `INSN_reg_C: tmp <= `_C; | |
| 13 | `INSN_reg_D: tmp <= `_D; | |
| 14 | `INSN_reg_E: tmp <= `_E; | |
| 15 | `INSN_reg_H: tmp <= `_H; | |
| 16 | `INSN_reg_L: tmp <= `_L; | |
| 17 | `INSN_reg_dHL: tmp <= rdata; | |
| 18 | endcase | |
| 19 | end | |
| 20 | end | |
| 21 | `endif | |
| 22 | ||
| 23 | `ifdef WRITEBACK | |
| 24 | `INSN_ALU_EXT: begin | |
| 25 | if (opcode[2:0] == `INSN_reg_dHL) begin | |
| 26 | if(cycle == 0) begin end | |
| 27 | else if(cycle == 1) begin | |
| 28 | `EXEC_WRITE(`_HL, alu_res) | |
| e7fe9dc2 | 29 | `_F <= {f_res,`_F[3:0]}; |
| c279b666 JW |
30 | end else begin |
| 31 | `EXEC_NEWCYCLE | |
| 32 | end | |
| 33 | end else begin | |
| 34 | case(opcode[2:0]) | |
| 35 | `INSN_reg_B: `_B <= alu_res; | |
| 36 | `INSN_reg_C: `_C <= alu_res; | |
| 37 | `INSN_reg_D: `_D <= alu_res; | |
| 38 | `INSN_reg_E: `_E <= alu_res; | |
| 39 | `INSN_reg_H: `_H <= alu_res; | |
| 40 | `INSN_reg_L: `_L <= alu_res; | |
| 41 | `INSN_reg_A: `_A <= alu_res; | |
| 42 | `INSN_reg_dHL: begin end /* eat dicks */ | |
| 43 | endcase | |
| 44 | `_F <= {f_res,`_F[3:0]}; | |
| 45 | `EXEC_NEWCYCLE | |
| 46 | end | |
| 47 | end | |
| 48 | `endif |