[fpgaboy.git] / insn_ldm16_a.v

// 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
Commit	Line	Data
f9000d73 JW	1	// If opcode[4], then ld A, x, else ld x, A
	2	// If opcode[1], then ld 16m8, else ld 8m8
	3
	4	`ifdef EXECUTE
fe3dc890	5	`INSN_LD16M_A: begin
f9000d73 JW	6	case (cycle)
	7	0: begin
	8	`EXEC_INC_PC
	9	`EXEC_READ(`_PC + 16'h0001)
	10	end
	11	1: begin
	12	`EXEC_INC_PC // we only hit here if 16m8
	13	`EXEC_READ(`_PC + 16'h0001)
	14	end
	15	2: if (opcode[4]) // LD A,x
f6fa1d6e	16	`EXEC_READ(({rdata, tmp}))
f9000d73	17	else
f6fa1d6e	18	`EXEC_WRITE(({rdata, tmp}), `_A)
f9000d73 JW	19	3: begin
	20	`EXEC_NEWCYCLE
	21	`EXEC_INC_PC
	22	end
	23	endcase
	24	end
	25	`endif
	26
	27	`ifdef WRITEBACK
fe3dc890	28	`INSN_LD16M_A: begin
f9000d73	29	case (cycle)
fe3dc890	30	0: begin end
f6fa1d6e JW	31	1: tmp <= rdata;
f6fa1d6e JW	32	2: begin end
f9000d73 JW	33	3: if (opcode[4]) `_A <= rdata;
	34	endcase
	35	end
	36	`endif
	37