insn_ldx_ahl.v

   1 `ifdef EXECUTE
   2         `INSN_LDx_AHL: begin
   3                 case (cycle)
   4                 0:      begin
   5                                 address <= {registers[`REG_H],registers[`REG_L]};
   6                                 if (opcode[3]) begin    // LDx A, (HL)
   7                                         rd <= 1;
   8                                 end else begin
   9                                         wr <= 1;
  10                                         wdata <= registers[`REG_A];
  11                                 end
  12                         end
  13                 1:      begin
  14                                 `EXEC_NEWCYCLE;
  15                                 `EXEC_INC_PC;
  16                         end
  17                 endcase
  18         end
  19 `endif
  20
  21 `ifdef WRITEBACK
  22         `INSN_LDx_AHL: begin
  23                 case (cycle)
  24                 0:      begin /* Type F */ end
  25                 1:      begin
  26                                 if (opcode[3])
  27                                         registers[`REG_A] <= rdata;
  28                                 {registers[`REG_H],registers[`REG_L]} <=
  29                                         opcode[4] ? // if set, LDD, else LDI
  30                                         ({registers[`REG_H],registers[`REG_L]} - 1) :
  31                                         ({registers[`REG_H],registers[`REG_L]} + 1);
  32                         end
  33                 endcase
  34         end
  35 `endif