X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/9c834ff2149ba2b9b4db71a1bb6b974235c88273..3ad960bdb71efcbb1dfd436163085da0d70eb699:/GBZ80Core.v

diff --git a/GBZ80Core.v b/GBZ80Core.v
index ae6ff00..f41805a 100644
--- a/GBZ80Core.v
+++ b/GBZ80Core.v
@@ -90,9 +90,9 @@
 
 module GBZ80Core(
 	input clk,
-	output reg [15:0] busaddress = 0,	/* BUS_* is latched on STATE_FETCH. */
+	output reg [15:0] busaddress,	/* BUS_* is latched on STATE_FETCH. */
 	inout [7:0] busdata,
-	output reg buswr = 0, output reg busrd = 0,
+	output reg buswr, output reg busrd,
 	input irq, input [7:0] jaddr);
 	
 	reg [1:0] state;					/* State within this bus cycle (see STATE_*). */
@@ -112,7 +112,7 @@ module GBZ80Core(
 	reg [7:0] buswdata;
 	assign busdata = buswr ? buswdata : 8'bzzzzzzzz;
 	
-	reg ie = 0, iedelay = 0;
+	reg ie, iedelay;
 	
 	initial begin
 		registers[ 0] <= 0;
@@ -191,213 +191,9 @@ module GBZ80Core(
 `define EXEC_NEWCYCLE \
 	newcycle <= 1; rd <= 1; wr <= 0
 			casex (opcode)
-			`INSN_LD_reg_imm8: begin
-				case (cycle)
-				0:	begin
-						`EXEC_INC_PC;
-						`EXEC_NEXTADDR_PCINC;
-						rd <= 1;
-					end
-				1:	begin
-						`EXEC_INC_PC;
-						if (opcode[5:3] == `INSN_reg_dHL) begin
-							address <= {registers[`REG_H], registers[`REG_L]};
-							wdata <= rdata;
-							rd <= 0;
-							wr <= 1;
-						end else begin
-							`EXEC_NEWCYCLE;
-						end
-					end
-				2:	begin
-						`EXEC_NEWCYCLE;
-					end
-				endcase
-			end
-			`INSN_HALT: begin
-				`EXEC_NEWCYCLE;
-				/* XXX Interrupts needed for HALT. */
-			end
-			`INSN_LD_HL_reg: begin
-				case (cycle)
-				0:	begin
-						case (opcode[2:0])
-						`INSN_reg_A:	wdata <= registers[`REG_A];
-						`INSN_reg_B:	wdata <= registers[`REG_B];
-						`INSN_reg_C:	wdata <= registers[`REG_C];
-						`INSN_reg_D:	wdata <= registers[`REG_D];
-						`INSN_reg_E:	wdata <= registers[`REG_E];
-						`INSN_reg_H:	wdata <= registers[`REG_H];
-						`INSN_reg_L:	wdata <= registers[`REG_L];
-						endcase
-						address <= {registers[`REG_H], registers[`REG_L]};
-						wr <= 1; rd <= 0;
-					end
-				1:	begin
-						`EXEC_INC_PC;
-						`EXEC_NEWCYCLE;
-					end
-				endcase
-			end
-			`INSN_LD_reg_HL: begin
-				case(cycle)
-				0:	begin
-						address <= {registers[`REG_H], registers[`REG_L]};
-						rd <= 1;
-					end
-				1:	begin
-						tmp <= rdata;
-						`EXEC_INC_PC;
-						`EXEC_NEWCYCLE;
-					end
-				endcase
-			end
-			`INSN_LD_reg_reg: begin
-				`EXEC_INC_PC;
-				`EXEC_NEWCYCLE;
-				case (opcode[2:0])
-				`INSN_reg_A:	tmp <= registers[`REG_A];
-				`INSN_reg_B:	tmp <= registers[`REG_B];
-				`INSN_reg_C:	tmp <= registers[`REG_C];
-				`INSN_reg_D:	tmp <= registers[`REG_D];
-				`INSN_reg_E:	tmp <= registers[`REG_E];
-				`INSN_reg_H:	tmp <= registers[`REG_H];
-				`INSN_reg_L:	tmp <= registers[`REG_L];
-				endcase
-			end
-			`INSN_LD_reg_imm16: begin
-				`EXEC_INC_PC;
-				case (cycle)
-				0:	begin
-						`EXEC_NEXTADDR_PCINC;
-						rd <= 1;
-					end
-				1:	begin
-						`EXEC_NEXTADDR_PCINC;
-						rd <= 1;
-					end
-				2: begin `EXEC_NEWCYCLE; end
-				endcase
-			end
-			`INSN_LD_SP_HL: begin
-				case (cycle)
-				0:	begin
-						tmp <= registers[`REG_H];
-					end
-				1:	begin
-						`EXEC_NEWCYCLE;
-						`EXEC_INC_PC;
-						tmp <= registers[`REG_L];
-					end
-				endcase
-			end
-			`INSN_PUSH_reg: begin	/* PUSH is 16 cycles! */
-				case (cycle)
-				0:	begin
-						wr <= 1;
-						address <= {registers[`REG_SPH],registers[`REG_SPL]}-1;
-						case (opcode[5:4])
-						`INSN_stack_AF:	wdata <= registers[`REG_A];
-						`INSN_stack_BC:	wdata <= registers[`REG_B];
-						`INSN_stack_DE:	wdata <= registers[`REG_D];
-						`INSN_stack_HL:	wdata <= registers[`REG_H];
-						endcase
-					end
-				1:	begin
-						wr <= 1;
-						address <= {registers[`REG_SPH],registers[`REG_SPL]}-2;
-						case (opcode[5:4])
-						`INSN_stack_AF:	wdata <= registers[`REG_F];
-						`INSN_stack_BC:	wdata <= registers[`REG_C];
-						`INSN_stack_DE:	wdata <= registers[`REG_E];
-						`INSN_stack_HL:	wdata <= registers[`REG_L];
-						endcase
-					end
-				2:	begin /* Twiddle thumbs. */ end
-				3:	begin
-						`EXEC_NEWCYCLE;
-						`EXEC_INC_PC;
-					end
-				endcase
-			end
-			`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
-			`INSN_LDH_AC: begin
-				case (cycle)
-				0:	begin
-						address <= {8'hFF,registers[`REG_C]};
-						if (opcode[4]) begin	// LD A,(C)
-							rd <= 1;
-						end else begin
-							wr <= 1;
-							wdata <= registers[`REG_A];
-						end
-					end
-				1:	begin
-						`EXEC_NEWCYCLE;
-						`EXEC_INC_PC;
-					end
-				endcase
-			end
-			`INSN_LDx_AHL: begin
-				case (cycle)
-				0:	begin
-						address <= {registers[`REG_H],registers[`REG_L]};
-						if (opcode[3]) begin	// LDx A, (HL)
-							rd <= 1;
-						end else begin
-							wr <= 1;
-							wdata <= registers[`REG_A];
-						end
-					end
-				1:	begin
-						`EXEC_NEWCYCLE;
-						`EXEC_INC_PC;
-					end
-				endcase
-			end
-			`INSN_ALU8: begin
-				if ((opcode[2:0] == `INSN_reg_dHL) && (cycle == 0)) begin
-					// fffffffff fuck your shit, read from (HL) :(
-					rd <= 1;
-					address <= {registers[`REG_H], registers[`REG_L]};
-				end else begin
-					`EXEC_NEWCYCLE;
-					`EXEC_INC_PC;
-					case (opcode[2:0])
-					`INSN_reg_A:	tmp <= registers[`REG_A];
-					`INSN_reg_B:	tmp <= registers[`REG_B];
-					`INSN_reg_C:	tmp <= registers[`REG_C];
-					`INSN_reg_D:	tmp <= registers[`REG_D];
-					`INSN_reg_E:	tmp <= registers[`REG_E];
-					`INSN_reg_H:	tmp <= registers[`REG_H];
-					`INSN_reg_L:	tmp <= registers[`REG_L];
-					`INSN_reg_dHL:	tmp <= rdata;
-					endcase
-				end
-			end
-			`INSN_ALU_A: begin
-				`EXEC_NEWCYCLE;
-				`EXEC_INC_PC;
-			end
-			`INSN_NOP: begin
-				`EXEC_NEWCYCLE;
-				`EXEC_INC_PC;
-			end
+			`define EXECUTE
+			`include "allinsns.v"
+			`undef EXECUTE
 			`INSN_RST: begin
 				case (cycle)
 				0:	begin
@@ -602,255 +398,9 @@ module GBZ80Core(
 		end
 		`STATE_WRITEBACK: begin
 			casex (opcode)
-			`INSN_LD_reg_imm8:
-				case (cycle)
-				0:	begin end
-				1:	case (opcode[5:3])
-					`INSN_reg_A:	begin registers[`REG_A] <= rdata; end
-					`INSN_reg_B:	begin registers[`REG_B] <= rdata; end
-					`INSN_reg_C:	begin registers[`REG_C] <= rdata; end
-					`INSN_reg_D:	begin registers[`REG_D] <= rdata; end
-					`INSN_reg_E:	begin registers[`REG_E] <= rdata; end
-					`INSN_reg_H:	begin registers[`REG_H] <= rdata; end
-					`INSN_reg_L:	begin registers[`REG_L] <= rdata; end
-					`INSN_reg_dHL:	begin /* Go off to cycle 2 */ end
-					endcase
-				2:	begin end
-				endcase
-			`INSN_HALT: begin
-				/* Nothing needs happen here. */
-				/* XXX Interrupts needed for HALT. */
-			end
-			`INSN_LD_HL_reg: begin
-				/* Nothing of interest here */
-			end
-			`INSN_LD_reg_HL: begin
-				case (cycle)
-				0:	begin end
-				1:	begin
-						case (opcode[5:3])
-						`INSN_reg_A:	registers[`REG_A] <= tmp;
-						`INSN_reg_B:	registers[`REG_B] <= tmp;
-						`INSN_reg_C:	registers[`REG_C] <= tmp;
-						`INSN_reg_D:	registers[`REG_D] <= tmp;
-						`INSN_reg_E:	registers[`REG_E] <= tmp;
-						`INSN_reg_H:	registers[`REG_H] <= tmp;
-						`INSN_reg_L:	registers[`REG_L] <= tmp;
-						endcase
-					end
-				endcase
-			end
-			`INSN_LD_reg_reg: begin
-				case (opcode[5:3])
-				`INSN_reg_A:	registers[`REG_A] <= tmp;
-				`INSN_reg_B:	registers[`REG_B] <= tmp;
-				`INSN_reg_C:	registers[`REG_C] <= tmp;
-				`INSN_reg_D:	registers[`REG_D] <= tmp;
-				`INSN_reg_E:	registers[`REG_E] <= tmp;
-				`INSN_reg_H:	registers[`REG_H] <= tmp;
-				`INSN_reg_L:	registers[`REG_L] <= tmp;
-				endcase
-			end
-			`INSN_LD_reg_imm16: begin
-				case (cycle)
-				0:	begin /* */ end
-				1:	begin
-						case (opcode[5:4])
-						`INSN_reg16_BC:	registers[`REG_C] <= rdata;
-						`INSN_reg16_DE:	registers[`REG_E] <= rdata;
-						`INSN_reg16_HL:	registers[`REG_L] <= rdata;
-						`INSN_reg16_SP:	registers[`REG_SPL] <= rdata;
-						endcase
-					end
-				2: begin
-						case (opcode[5:4])
-						`INSN_reg16_BC:	registers[`REG_B] <= rdata;
-						`INSN_reg16_DE:	registers[`REG_D] <= rdata;
-						`INSN_reg16_HL:	registers[`REG_H] <= rdata;
-						`INSN_reg16_SP:	registers[`REG_SPH] <= rdata;
-						endcase
-					end
-				endcase
-			end
-			`INSN_LD_SP_HL: begin
-				case (cycle)
-				0:	registers[`REG_SPH] <= tmp;
-				1: registers[`REG_SPL] <= tmp;
-				endcase
-			end
-			`INSN_PUSH_reg: begin	/* PUSH is 16 cycles! */
-				case (cycle)
-				0:	begin /* type F */ end
-				1:	begin /* type F */ end
-				2:	begin /* type F */ end
-				3:	{registers[`REG_SPH],registers[`REG_SPL]} <=
-						{registers[`REG_SPH],registers[`REG_SPL]} - 2;
-				endcase
-			end
-			`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
-			`INSN_LDH_AC: begin
-				case (cycle)
-				0:	begin /* Type F */ end
-				1:	if (opcode[4])
-						registers[`REG_A] <= rdata;
-				endcase
-			end
-			`INSN_LDx_AHL: begin
-				case (cycle)
-				0:	begin /* Type F */ end
-				1:	begin
-						if (opcode[3])
-							registers[`REG_A] <= rdata;
-						{registers[`REG_H],registers[`REG_L]} <=
-							opcode[4] ? // if set, LDD, else LDI
-							({registers[`REG_H],registers[`REG_L]} - 1) :
-							({registers[`REG_H],registers[`REG_L]} + 1);
-					end
-				endcase
-			end
-			`INSN_ALU8: begin
-				if ((opcode[2:0] == `INSN_reg_dHL) && (cycle == 0)) begin
-					/* Sit on our asses. */
-				end else begin		/* Actually do the computation! */
-					case (opcode[5:3])
-					`INSN_alu_ADD: begin
-						registers[`REG_A] <=
-							registers[`REG_A] + tmp;
-						registers[`REG_F] <=
-							{ /* Z */ ((registers[`REG_A] + tmp) == 0) ? 1'b1 : 1'b0,
-							  /* N */ 1'b0,
-							  /* H */ (({1'b0,registers[`REG_A][3:0]} + {1'b0,tmp[3:0]}) >> 4 == 1) ? 1'b1 : 1'b0,
-							  /* C */ (({1'b0,registers[`REG_A]} + {1'b0,tmp}) >> 8 == 1) ? 1'b1 : 1'b0,
-							  registers[`REG_F][3:0]
-							};
-					end
-					`INSN_alu_ADC: begin
-						registers[`REG_A] <=
-							registers[`REG_A] + tmp + {7'b0,registers[`REG_F][4]};
-						registers[`REG_F] <=
-							{ /* Z */ ((registers[`REG_A] + tmp + {7'b0,registers[`REG_F][4]}) == 0) ? 1'b1 : 1'b0,
-							  /* N */ 1'b0,
-							  /* H */ (({1'b0,registers[`REG_A][3:0]} + {1'b0,tmp[3:0]} + {4'b0,registers[`REG_F][4]}) >> 4 == 1) ? 1'b1 : 1'b0,
-							  /* C */ (({1'b0,registers[`REG_A]} + {1'b0,tmp} + {8'b0,registers[`REG_F][4]}) >> 8 == 1) ? 1'b1 : 1'b0,
-							  registers[`REG_F][3:0]
-							};
-					end
-					`INSN_alu_SUB: begin
-						registers[`REG_A] <=
-							registers[`REG_A] - tmp;
-						registers[`REG_F] <=
-							{ /* Z */ ((registers[`REG_A] - tmp) == 0) ? 1'b1 : 1'b0,
-							  /* N */ 1'b1,
-							  /* H */ (({1'b0,registers[`REG_A][3:0]} - {1'b0,tmp[3:0]}) >> 4 == 1) ? 1'b1 : 1'b0,
-							  /* C */ (({1'b0,registers[`REG_A]} - {1'b0,tmp}) >> 8 == 1) ? 1'b1 : 1'b0,
-							  registers[`REG_F][3:0]
-							};
-					end
-					`INSN_alu_SBC: begin
-						registers[`REG_A] <=
-							registers[`REG_A] - (tmp + {7'b0,registers[`REG_F][4]});
-						registers[`REG_F] <=
-							{ /* Z */ ((registers[`REG_A] - (tmp + {7'b0,registers[`REG_F][4]})) == 0) ? 1'b1 : 1'b0,
-							  /* N */ 1'b1,
-							  /* H */ (({1'b0,registers[`REG_A][3:0]} - ({1'b0,tmp[3:0]} + {4'b0,registers[`REG_F][4]})) >> 4 == 1) ? 1'b1 : 1'b0,
-							  /* C */ (({1'b0,registers[`REG_A]} - ({1'b0,tmp} + {8'b0,registers[`REG_F][4]})) >> 8 == 1) ? 1'b1 : 1'b0,
-							  registers[`REG_F][3:0]
-							};
-					end
-					`INSN_alu_AND: begin
-						registers[`REG_A] <=
-							registers[`REG_A] & tmp;
-						registers[`REG_F] <=
-							{ /* Z */ ((registers[`REG_A] & tmp) == 0) ? 1'b1 : 1'b0,
-							  3'b010,
-							  registers[`REG_F][3:0]
-							};
-					end
-					`INSN_alu_OR: begin
-						registers[`REG_A] <=
-							registers[`REG_A] | tmp;
-						registers[`REG_F] <=
-							{ /* Z */ ((registers[`REG_A] | tmp) == 0) ? 1'b1 : 1'b0,
-							  3'b000,
-							  registers[`REG_F][3:0]
-							};
-					end
-					`INSN_alu_XOR: begin
-						registers[`REG_A] <=
-							registers[`REG_A] ^ tmp;
-						registers[`REG_F] <=
-							{ /* Z */ ((registers[`REG_A] ^ tmp) == 0) ? 1'b1 : 1'b0,
-							  3'b000,
-							  registers[`REG_F][3:0]
-							};
-					end
-					`INSN_alu_CP: begin
-						registers[`REG_F] <=
-							{ /* Z */ ((registers[`REG_A] - tmp) == 0) ? 1'b1 : 1'b0,
-							  /* N */ 1'b1,
-							  /* H */ (({1'b0,registers[`REG_A][3:0]} - {1'b0,tmp[3:0]}) >> 4 == 1) ? 1'b1 : 1'b0,
-							  /* C */ (({1'b0,registers[`REG_A]} - {1'b0,tmp}) >> 8 == 1) ? 1'b1 : 1'b0,
-							  registers[`REG_F][3:0]
-							};
-					end
-					default:
-						$stop;
-					endcase
-				end
-			end
-			`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,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
-			`INSN_NOP: begin /* NOP! */ end
+			`define WRITEBACK
+			`include "allinsns.v"
+			`undef WRITEBACK
 			`INSN_RST: begin
 				case (cycle)
 				0:	begin /* type F */ end