X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/5f7913a508f18ca9664223dde5ae16608595a08b..81358c71b258a72a2777bba0a0b4a82a7cae298a:/insn_pop_reg.v

diff --git a/insn_pop_reg.v b/insn_pop_reg.v
new file mode 100644
index 0000000..9d4acbd
--- /dev/null
+++ b/insn_pop_reg.v
@@ -0,0 +1,44 @@
+`ifdef EXECUTE
+	`INSN_POP_reg: begin	/* POP is 12 cycles! */
+		case (cycle)
+		0:	begin
+				rd <= 1;
+				address <= {registers[`REG_SPH],registers[`REG_SPL]};
+			end
+		1:	begin
+				rd <= 1;
+				address <= {registers[`REG_SPH],registers[`REG_SPL]} + 1;
+			end
+		2:	begin
+				`EXEC_NEWCYCLE;
+				`EXEC_INC_PC;
+			end
+		endcase
+	end
+`endif
+
+`ifdef WRITEBACK
+	`INSN_POP_reg: begin	/* POP is 12 cycles! */
+		case (cycle)
+		0:	begin end
+		1:	begin
+				case (opcode[5:4])
+				`INSN_stack_AF:	registers[`REG_F] <= rdata;
+				`INSN_stack_BC:	registers[`REG_C] <= rdata;
+				`INSN_stack_DE:	registers[`REG_E] <= rdata;
+				`INSN_stack_HL:	registers[`REG_L] <= rdata;
+				endcase
+			end
+		2:	begin
+				case (opcode[5:4])
+				`INSN_stack_AF:	registers[`REG_A] <= rdata;
+				`INSN_stack_BC:	registers[`REG_B] <= rdata;
+				`INSN_stack_DE:	registers[`REG_D] <= rdata;
+				`INSN_stack_HL:	registers[`REG_H] <= rdata;
+				endcase
+				{registers[`REG_SPH],registers[`REG_SPL]} <=
+					{registers[`REG_SPH],registers[`REG_SPL]} + 2;
+			end
+		endcase
+	end
+`endif