core/insn_bit.v

   1 `define INSN_BIT                9'b101xxxxxx
   2
   3 `ifdef EXECUTE
   4         `INSN_BIT: begin
   5                 if ((opcode[2:0] == `INSN_reg_dHL) && (cycle == 0)) begin
   6                         `EXEC_READ(`_HL)
   7                 end else if ((opcode[2:0] == `INSN_reg_dHL) && (cycle == 2)) begin
   8                         `EXEC_NEWCYCLE
   9                 end else begin
  10                         `EXEC_INC_PC
  11                         case (opcode[2:0])
  12                         `INSN_reg_A:    tmp <= `_A;
  13                         `INSN_reg_B:    tmp <= `_B;
  14                         `INSN_reg_C:    tmp <= `_C;
  15                         `INSN_reg_D:    tmp <= `_D;
  16                         `INSN_reg_E:    tmp <= `_E;
  17                         `INSN_reg_H:    tmp <= `_H;
  18                         `INSN_reg_L:    tmp <= `_L;
  19                         `INSN_reg_dHL:  tmp <= rdata;
  20                         endcase
  21                         if (opcode[2:0] != `INSN_reg_dHL) begin
  22                                 `EXEC_NEWCYCLE
  23                         end
  24                 end
  25         end
  26 `endif
  27
  28 `ifdef WRITEBACK
  29         `INSN_BIT: begin
  30                 if ((opcode[2:0] != `INSN_reg_dHL) || (cycle == 1))
  31                         `_F <= {~tmp[opcode[5:3]], 2'b01, `_F[4:0]};
  32         end
  33 `endif