X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/03202f62407e24bd964016dccc06de95df622e3c..f6fa1d6e1393de5d18302b8674ed1616afdfcefb:/insn_ldm16_a.v

diff --git a/insn_ldm16_a.v b/insn_ldm16_a.v
new file mode 100644
index 0000000..d8356f7
--- /dev/null
+++ b/insn_ldm16_a.v
@@ -0,0 +1,37 @@
+// If opcode[4], then ld A, x, else ld x, A
+// If opcode[1], then ld 16m8, else ld 8m8
+
+`ifdef EXECUTE
+	`INSN_LD16M_A: begin
+		case (cycle)
+		0:	begin
+				`EXEC_INC_PC
+				`EXEC_READ(`_PC + 16'h0001)
+			end
+		1:	begin
+				`EXEC_INC_PC			// we only hit here if 16m8
+				`EXEC_READ(`_PC + 16'h0001)
+			end
+		2:	if (opcode[4])	// LD A,x
+				`EXEC_READ(({rdata, tmp}))
+			else
+				`EXEC_WRITE(({rdata, tmp}), `_A)
+		3:	begin
+				`EXEC_NEWCYCLE
+				`EXEC_INC_PC
+			end
+		endcase
+	end
+`endif
+
+`ifdef WRITEBACK
+	`INSN_LD16M_A: begin
+		case (cycle)
+		0:	begin end
+		1:	tmp <= rdata;
+		2:	begin end
+		3:	if (opcode[4]) `_A <= rdata;
+		endcase
+	end
+`endif
+