Move the core to core/

[fpgaboy.git] / core / insn_incdec_reg8.v

diff --git a/core/insn_incdec_reg8.v b/core/insn_incdec_reg8.v
new file mode 100644 (file)
index 0000000..58582b6
--- /dev/null
+++ b/core/insn_incdec_reg8.v
@@ -0,0 +1,34 @@
+`ifdef EXECUTE
+       `INSN_INCDEC_reg8: begin
+               `EXEC_INC_PC
+               `EXEC_NEWCYCLE
+               case (opcode[5:3])
+               `INSN_reg_A:    tmp <= `_A;
+               `INSN_reg_B:    tmp <= `_B;
+               `INSN_reg_C:    tmp <= `_C;
+               `INSN_reg_D:    tmp <= `_D;
+               `INSN_reg_E:    tmp <= `_E;
+               `INSN_reg_H:    tmp <= `_H;
+               `INSN_reg_L:    tmp <= `_L;
+               endcase
+       end
+`endif
+
+`ifdef WRITEBACK
+       `INSN_INCDEC_reg8: begin
+               case (opcode[5:3])
+               `INSN_reg_A:    `_A <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+               `INSN_reg_B:    `_B <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+               `INSN_reg_C:    `_C <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+               `INSN_reg_D:    `_D <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+               `INSN_reg_E:    `_E <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+               `INSN_reg_H:    `_H <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+               `INSN_reg_L:    `_L <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+               endcase
+               `_F <= {
+                               ((tmp + (opcode[0] ? 8'hFF : 8'h01)) == 8'h00) ? 1'b1 : 1'b0,
+                               1'b0,
+                               (({1'b0,tmp[3:0]} + (opcode[0] ? 5'h1F : 5'h01)) >> 4) ? 1'b1 : 1'b0,
+                               `_F[4:0]};
+       end
+`endif