X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/eb0f2fe1637a4c6b4532ae08ff7b0af3bf39aef0..3ad960bdb71efcbb1dfd436163085da0d70eb699:/insn_alu_a.v

diff --git a/insn_alu_a.v b/insn_alu_a.v
new file mode 100644
index 0000000..fe3315a
--- /dev/null
+++ b/insn_alu_a.v
@@ -0,0 +1,39 @@
+`ifdef EXECUTE
+	`INSN_ALU_A: begin
+		`EXEC_NEWCYCLE;
+		`EXEC_INC_PC;
+	end
+`endif
+
+`ifdef WRITEBACK
+	`INSN_ALU_A: begin
+		case(opcode[5:3])
+		`INSN_alu_RLCA: begin
+			registers[`REG_A] <= {registers[`REG_A][6:0],registers[`REG_A][7]};
+			registers[`REG_F] <= {registers[`REG_F][7:5],registers[`REG_A][7],registers[`REG_F][3:0]};
+		end
+		`INSN_alu_RRCA: begin
+			registers[`REG_A] <= {registers[`REG_A][0],registers[`REG_A][7:1]};
+			registers[`REG_F] <= {registers[`REG_F][7:5],registers[`REG_A][0],registers[`REG_F][3:0]};
+		end
+		`INSN_alu_RLA: begin
+			registers[`REG_A] <= {registers[`REG_A][6:0],registers[`REG_F][4]};
+			registers[`REG_F] <= {registers[`REG_F][7:5],registers[`REG_A][7],registers[`REG_F][3:0]};
+		end
+		`INSN_alu_RRA: begin
+			registers[`REG_A] <= {registers[`REG_A][4],registers[`REG_A][7:1]};
+			registers[`REG_F] <= {registers[`REG_F][7:5],registers[`REG_A][0],registers[`REG_F][3:0]};
+		end
+		`INSN_alu_CPL: begin
+			registers[`REG_A] <= ~registers[`REG_A];
+			registers[`REG_F] <= {registers[`REG_F][7],1'b1,1'b1,registers[`REG_F][4:0]};
+		end
+		`INSN_alu_SCF: begin
+			registers[`REG_F] <= {registers[`REG_F][7:5],1'b1,registers[`REG_F][3:0]};
+		end
+		`INSN_alu_CCF: begin
+			registers[`REG_F] <= {registers[`REG_F][7:5],~registers[`REG_F][4],registers[`REG_F][3:0]};
+		end
+		endcase
+	end
+`endif