| | 1 | `define INSN_LD16M_A 9'b0111x1010 // 1111 for ld A, x; 1110 for ld x, A; bit 1 specifies 16m8 or 8m8 |
| | 2 | |
| | 3 | // If opcode[4], then ld A, x, else ld x, A |
| | 4 | // If opcode[1], then ld 16m8, else ld 8m8 |
| | 5 | |
| | 6 | `ifdef EXECUTE |
| | 7 | `INSN_LD16M_A: begin |
| | 8 | case (cycle) |
| | 9 | 0: begin |
| | 10 | `EXEC_INC_PC |
| | 11 | `EXEC_READ(`_PC + 16'h0001) |
| | 12 | end |
| | 13 | 1: begin |
| | 14 | `EXEC_INC_PC // we only hit here if 16m8 |
| | 15 | `EXEC_READ(`_PC + 16'h0001) |
| | 16 | end |
| | 17 | 2: if (opcode[4]) // LD A,x |
| | 18 | `EXEC_READ(({rdata, tmp})) |
| | 19 | else |
| | 20 | `EXEC_WRITE(({rdata, tmp}), `_A) |
| | 21 | 3: begin |
| | 22 | `EXEC_NEWCYCLE |
| | 23 | `EXEC_INC_PC |
| | 24 | end |
| | 25 | endcase |
| | 26 | end |
| | 27 | `endif |
| | 28 | |
| | 29 | `ifdef WRITEBACK |
| | 30 | `INSN_LD16M_A: begin |
| | 31 | case (cycle) |
| | 32 | 0: begin end |
| | 33 | 1: tmp <= rdata; |
| | 34 | 2: begin end |
| | 35 | 3: if (opcode[4]) `_A <= rdata; |
| | 36 | endcase |
| | 37 | end |
| | 38 | `endif |
| | 39 | |
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