Subversion Repositories uart2bus

//---------------------------------------------------------------------------------------
// uart test bench   
//
//---------------------------------------------------------------------------------------
 
`include "timescale.v"
 
module test;
//---------------------------------------------------------------------------------------
// include uart tasks 
`include "uart_tasks.v" 
 
// internal signal  
reg clock;		// global clock 
reg reset;		// global reset 
reg [6:0] counter;
 
//---------------------------------------------------------------------------------------
// test bench implementation 
// global signals generation  
initial
begin
	counter = 0;
	clock = 0;
	reset = 1;
	#40 reset = 0;
end 
 
// clock generator - 40MHz clock 
always 
begin 
	#12 clock = 0;
	#13 clock = 1;
end 
 
// test bench dump variables 
initial 
begin 
	$dumpfile("test.vcd");
	//$dumpall;
	$dumpvars(0, test);
end 
 
//------------------------------------------------------------------
// test bench transmitter and receiver 
// uart transmit - test bench control 
 
initial 
begin 
	// defualt value of serial output 
	serial_out = 1;
 
	// transmit a write command to internal register file 
	// command string: "w 4cd9 1a" + CR 
	send_serial (8'h77, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0); 
	#100;
	send_serial (8'h20, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h34, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h63, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h64, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h39, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h20, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h31, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h61, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h0d, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	// transmit a read command from register file 
	// command string: "r 1a" + CR 
	send_serial (8'h72, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0); 
	#100;
	send_serial (8'h20, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h31, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h61, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
	send_serial (8'h0d, `BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8, 0);
	#100;
 
	// delay and finish 
	#900000;
	$finish;
end 
 
// uart receive 
initial 
begin 
	// default value for serial receiver and serial input 
	serial_in = 1;
	get_serial_data = 0;		// data received from get_serial task 
	get_serial_status = 0;		// status of get_serial task  
end 
 
// serial sniffer loop 
always 
begin 
	// call serial sniffer 
	get_serial(`BAUD_115200, `PARITY_EVEN, `PARITY_OFF, `NSTOPS_1, `NBITS_8);
 
	// check serial receiver status 
	// byte received OK 
	if (get_serial_status & `RECEIVE_RESULT_OK)
	begin
		// check if not a control character (above and including space ascii code)
		if (get_serial_data >= 8'h20) 
			$display("received byte 0x%h (\"%c\") at %t ns", get_serial_data, get_serial_data, $time);
		else 
			$display("received byte 0x%h (\"%c\") at %t ns", get_serial_data, 8'hb0, $time);
	end 
 
	// false start error 
	if (get_serial_status & `RECEIVE_RESULT_FALSESTART)
		$display("Error (get_char): false start condition at %t", $realtime);
 
	// bad parity error 		
	if (get_serial_status & `RECEIVE_RESULT_BADPARITY)
		$display("Error (get_char): bad parity condition at %t", $realtime);
 
	// bad stop bits sequence 	
	if (get_serial_status & `RECEIVE_RESULT_BADSTOP)
		$display("Error (get_char): bad stop bits sequence at %t", $realtime);
end 
 
//------------------------------------------------------------------
// device under test 
// DUT interface 
wire	[7:0]	int_address;	// address bus to register file 
wire	[7:0]	int_wr_data;	// write data to register file 
wire			int_write;		// write control to register file 
wire			int_read;		// read control to register file 
wire	[7:0]	int_rd_data;	// data read from register file 
wire			int_req;		// bus access request signal 
wire			int_gnt;		// bus access grant signal 
wire			ser_in;			// DUT serial input 
wire			ser_out;		// DUT serial output 
 
// DUT instance 
uart2bus_top uart2bus1
(
	.clock(clock), .reset(reset),
	.ser_in(ser_in), .ser_out(ser_out),
	.int_address(int_address), .int_wr_data(int_wr_data), .int_write(int_write),
	.int_rd_data(int_rd_data), .int_read(int_read), 
	.int_req(int_req), .int_gnt(int_gnt) 
);
// bus grant is always active 
assign int_gnt = 1'b1;
 
// serial interface to test bench 
assign ser_in = serial_out;
always @ (posedge clock) serial_in = ser_out;
 
// register file model 
reg_file_model reg_file1 
(
	.clock(clock), .reset(reset),
	.int_address(int_address), .int_wr_data(int_wr_data), .int_write(int_write),
	.int_rd_data(int_rd_data), .int_read(int_read)
);
 
endmodule
//---------------------------------------------------------------------------------------
//						Th.. Th.. Th.. Thats all folks !!!
//---------------------------------------------------------------------------------------