gpsnavidatagen_4ch.v

基于verilog语言的ＧＰＳ模拟源代码

	   begin
	   	if (Sat1_status == IDLE)
	   		Sat1_status <= Sat1_nextstatus;
	    else if (NB1)
	 		Sat1_status <= Sat1_nextstatus;
	 	
	 	if (Sat2_status == IDLE)
	 		Sat2_status <= Sat2_nextstatus;
	 	else if (NB2)
	 		Sat2_status <= Sat2_nextstatus;
	 	
	 	if (Sat3_status == IDLE)
	 		Sat3_status <= Sat3_nextstatus;
	 	else if (NB3)
	 		Sat3_status <= Sat3_nextstatus;
	 	
	 	if (Sat4_status == IDLE)
	 		Sat4_status <= Sat4_nextstatus;
	 	else if (NB4)
	 		Sat4_status <= Sat4_nextstatus;
	   end

// Statuse Mechine; Satellite 1
always @ (Sat1_status or Sat1_NavBit_Cnt or Sat1_Word_Cnt)
 begin
 	case (Sat1_status)
 		IDLE: 
 			Sat1_nextstatus <= TLMWORD;
 			
 		TLMWORD:
 			if (Sat1_NavBit_Cnt<23)
 				Sat1_nextstatus <= TLMWORD;
 			else
 				Sat1_nextstatus <= PARITY;
 		
 		PARITY:
 			if (Sat1_NavBit_Cnt == 29)
 			  begin
 			  	Sat1_nextstatus <= IDLE;
 			  	
 				if (Sat1_Word_Cnt == 9)
 					Sat1_nextstatus <= TLMWORD;
 					
 				if (Sat1_Word_Cnt == 0)
 					Sat1_nextstatus <= HOWWORD;
 					
 				if ((Sat1_Word_Cnt>0)&&(Sat1_Word_Cnt<9))
 					Sat1_nextstatus <= NAVIDATAWORD;
 			  end
 			else
 				Sat1_nextstatus <= PARITY;
 				
 		HOWWORD:
 			if (Sat1_NavBit_Cnt<23)
 				Sat1_nextstatus <= HOWWORD;
 			else
 				Sat1_nextstatus <= PARITY;
 				
 		NAVIDATAWORD:
 			if (Sat1_NavBit_Cnt<23)
 				Sat1_nextstatus <= NAVIDATAWORD;
 			else
 				Sat1_nextstatus <= PARITY;  
 		default: Sat1_nextstatus <= IDLE; 
 	endcase	
 end

// Statuse Mechine; Satellite 2
always @ (Sat2_status or Sat2_NavBit_Cnt or Sat2_Word_Cnt)
 begin
 	case (Sat2_status)
 		IDLE: 
 			Sat2_nextstatus <= TLMWORD;
 			
 		TLMWORD:
 			if (Sat2_NavBit_Cnt<23)
 				Sat2_nextstatus <= TLMWORD;
 			else
 				Sat2_nextstatus <= PARITY;
 		
 		PARITY:
 			if (Sat2_NavBit_Cnt == 29)
 			  begin
 			  	Sat2_nextstatus <= IDLE;
 			  	
 				if (Sat2_Word_Cnt == 9)
 					Sat2_nextstatus <= TLMWORD;
 					
 				if (Sat2_Word_Cnt == 0)
 					Sat2_nextstatus <= HOWWORD;
 					
 				if ((Sat2_Word_Cnt>0)&&(Sat2_Word_Cnt<9))
 					Sat2_nextstatus <= NAVIDATAWORD;
 			  end
 			else
 				Sat2_nextstatus <= PARITY;
 				
 		HOWWORD:
 			if (Sat2_NavBit_Cnt<23)
 				Sat2_nextstatus <= HOWWORD;
 			else   
 				Sat2_nextstatus <= PARITY;
 				
 		NAVIDATAWORD:
 			if (Sat2_NavBit_Cnt<23)
 				Sat2_nextstatus <= NAVIDATAWORD;
 			else   
 				Sat2_nextstatus <= PARITY;
 		default: Sat2_nextstatus <= IDLE; 
 	endcase	
 end

// Statuse Mechine; Satellite 3
always @ (Sat3_status or Sat3_NavBit_Cnt or Sat3_Word_Cnt)
 begin       
 	case (Sat3_status)
 		IDLE: 
 			Sat3_nextstatus <= TLMWORD;
 			
 		TLMWORD:
 			if (Sat3_NavBit_Cnt<23)
 				Sat3_nextstatus <= TLMWORD;
 			else   
 				Sat3_nextstatus <= PARITY;
 		
 		PARITY:
 			if (Sat3_NavBit_Cnt == 29)
 			  begin
 			  	Sat3_nextstatus <= IDLE;
 			  	
 				if (Sat3_Word_Cnt == 9)
 					Sat3_nextstatus <= TLMWORD;
 					
 				if (Sat3_Word_Cnt == 0)
 					Sat3_nextstatus <= HOWWORD;
 					
 				if ((Sat3_Word_Cnt>0)&&(Sat3_Word_Cnt<9))
 					Sat3_nextstatus <= NAVIDATAWORD;
 			  end
 			else
 				Sat3_nextstatus <= PARITY;
 				
 		HOWWORD:
 			if (Sat3_NavBit_Cnt<23)
 				Sat3_nextstatus <= HOWWORD;
 			else   
 				Sat3_nextstatus <= PARITY;
 				
 		NAVIDATAWORD:
 			if (Sat3_NavBit_Cnt<23)
 				Sat3_nextstatus <= NAVIDATAWORD;
 			else   
 				Sat3_nextstatus <= PARITY;
 		default: Sat3_nextstatus <= IDLE; 
 	endcase	
 end

// Statuse Mechine; Satellite 4
always @ (Sat4_status or Sat4_NavBit_Cnt or Sat4_Word_Cnt)
 begin
 	case (Sat4_status)
 		IDLE: 
 			Sat4_nextstatus <= TLMWORD;
 			
 		TLMWORD:
 			if (Sat4_NavBit_Cnt<23)
 				Sat4_nextstatus <= TLMWORD;
 			else   
 				Sat4_nextstatus <= PARITY;
 		
 		PARITY:
 			if (Sat4_NavBit_Cnt == 29)
 			  begin
 			  	Sat4_nextstatus <= IDLE;
 			  	
 				if (Sat4_Word_Cnt == 9)
 					Sat4_nextstatus <= TLMWORD;
 					   
 				if (Sat4_Word_Cnt == 0)
 					Sat4_nextstatus <= HOWWORD;
 					
 				if ((Sat4_Word_Cnt>0)&&(Sat4_Word_Cnt<9))
 					Sat4_nextstatus <= NAVIDATAWORD;
 			  end
 			else
 				Sat4_nextstatus <= PARITY;
 				   
 		HOWWORD:   
 			if (Sat4_NavBit_Cnt<23)
 				Sat4_nextstatus <= HOWWORD;
 			else   
 				Sat4_nextstatus <= PARITY;
 				
 		NAVIDATAWORD:
 			if (Sat4_NavBit_Cnt<23)
 				Sat4_nextstatus <= NAVIDATAWORD;
 			else   
 				Sat4_nextstatus <= PARITY;
 		default: Sat4_nextstatus <= IDLE; 
 	endcase	
 end

// Generate the navigation data for satellite 1
always @(posedge in_clk or negedge in_Resetn)
	begin
	 if (!in_Resetn)
	 	NaviData1 <= 1;
	 else
	 	case (Sat1_status)
	 		TLMWORD:
	 			case (Sat1_NavBit_Cnt)
	 				0,
	 				4,
	 				6,
	 				7: NaviData1 <=1;
	 				
	 				1,
	 				2,
	 				3,
	 				5: NaviData1 <=0;
	 				
	 				default: 
	 				 if(NB1)
	 				 	NaviData1 <= ~NaviData1; 
	 				 	//NaviData1 <= 0;
	 			endcase
	 			
	 		PARITY:
	 			case (Sat1_NavBit_Cnt)
	 				24: NaviData1 <= Sat1_PrtW[0];
	 				25: NaviData1 <= Sat1_PrtW[1];
	 				26: NaviData1 <= Sat1_PrtW[2];
	 				27: NaviData1 <= Sat1_PrtW[3];
	 				28: 
	 					begin
	 					 if (Sat1_Word_Cnt == 9)
	 					  NaviData1 <= 0;
	 					 else
	 					  NaviData1 <= Sat1_PrtW[4];
	 					end
	 					
	 				29: 
	 					begin
	 					 if (Sat1_Word_Cnt == 9)
	 					  NaviData1 <= 0;
	 					 else
	 					  NaviData1 <= Sat1_PrtW[5];
	 					  
	 					end
	 			endcase
	 			
	 		HOWWORD: