insn_alu_a.v

   1 `ifdef EXECUTE
   2         `INSN_ALU_A: begin
   3                 `EXEC_NEWCYCLE;
   4                 `EXEC_INC_PC;
   5         end
   6 `endif
   7
   8 `ifdef WRITEBACK
   9         `INSN_ALU_A: begin
  10                 case(opcode[5:3])
  11                 `INSN_alu_RLCA: begin
  12                         registers[`REG_A] <= {registers[`REG_A][6:0],registers[`REG_A][7]};
  13                         registers[`REG_F] <= {registers[`REG_F][7:5],registers[`REG_A][7],registers[`REG_F][3:0]};
  14                 end
  15                 `INSN_alu_RRCA: begin
  16                         registers[`REG_A] <= {registers[`REG_A][0],registers[`REG_A][7:1]};
  17                         registers[`REG_F] <= {registers[`REG_F][7:5],registers[`REG_A][0],registers[`REG_F][3:0]};
  18                 end
  19                 `INSN_alu_RLA: begin
  20                         registers[`REG_A] <= {registers[`REG_A][6:0],registers[`REG_F][4]};
  21                         registers[`REG_F] <= {registers[`REG_F][7:5],registers[`REG_A][7],registers[`REG_F][3:0]};
  22                 end
  23                 `INSN_alu_RRA: begin
  24                         registers[`REG_A] <= {registers[`REG_A][4],registers[`REG_A][7:1]};
  25                         registers[`REG_F] <= {registers[`REG_F][7:5],registers[`REG_A][0],registers[`REG_F][3:0]};
  26                 end
  27                 `INSN_alu_CPL: begin
  28                         registers[`REG_A] <= ~registers[`REG_A];
  29                         registers[`REG_F] <= {registers[`REG_F][7],1'b1,1'b1,registers[`REG_F][4:0]};
  30                 end
  31                 `INSN_alu_SCF: begin
  32                         registers[`REG_F] <= {registers[`REG_F][7:5],1'b1,registers[`REG_F][3:0]};
  33                 end
  34                 `INSN_alu_CCF: begin
  35                         registers[`REG_F] <= {registers[`REG_F][7:5],~registers[`REG_F][4],registers[`REG_F][3:0]};
  36                 end
  37                 endcase
  38         end
  39 `endif