top.v

PS2的源代码VHDL语言实现

//-----------------------------------------------------------------------------
//
// Author: John Clayton
// Date  : April 30, 2001
// Update: April 30, 2001 Copied this file from "lcd_3.v" for use as top level
// Update: May    3, 2001 Included instantiations of VHDL code, to test mixed
//                        language support of the XILINX foundation 3.1 tools.
// Update: June   1, 2001 Brigham Young's 200th birthday!
//                        Started project "build_4" using ps2 interface and
//                        the rs232 interface code.
// Update: June   5, 2001 Finished debugging the keyboard ps2 interface.
//                        Removed debug outputs from keyboard interface.
// Update: June   7, 2001 Added the new ps2_mouse_interface module. ("build_5")
//
// Description
//-----------------------------------------------------------------------------
// This targets an XC2S200 board which was created for educational purposes.
//
// There are:
//    8  LEDs (led[7:0])
//    4  switches (switch[3:0])
//    1  clock of 32.000 MHz clock, present on GCLK1
//    1  clock of 49.152 MHz clock, present on GCLK0
//    4  lines of ps2 clock input (port A in documentation notes)
//    4  lines of ps2 data input (port A in documentation notes)
//    16 lines of LCD panel control (port B in documentation notes)
//    2  lines of rs232 serial connection (port C in documentation notes)
//-----------------------------------------------------------------------------


`resetall
`timescale 1ns/100ps

module top (
  sys_clk_0,
  sys_clk_1,
  switch,
  led,
  ps2_clk,
  ps2_data,
  lcd_drive,
  rs232_rxd,
  rs232_txd
  );
  
// I/O declarations
input sys_clk_0;      // 49.152 MHz
input sys_clk_1;      // 32.000 MHz
input [3:0] switch;
input rs232_rxd;

inout [3:0] ps2_clk;
inout [3:0] ps2_data;

output [7:0] led;

output [15:0] lcd_drive;
output rs232_txd;

// Internal signal declarations

wire [9:0] crosshair_x_pos;
wire [9:0] crosshair_y_pos;
wire mouse_left;
wire mouse_right;

wire [7:0] ps2_ascii;
wire [7:0] ps2_status;
wire [7:0] rs232_rx_character;

wire [8:0] x_increment;
wire [8:0] y_increment;

wire [7:0] temp1;
wire [7:0] temp2;

wire reset = switch[0];
//wire [2:0] rs232_rx_error;
//wire ps2_key_data_ready;
//wire ps2_key_released;
//wire ps2_key_pressed = ~ps2_key_released;
//wire rx232_tx_load_request;
//wire rs232_rx_data_ready;

wire [7:0] debug;

//--------------------------------------------------------------------------
// Instantiations
//--------------------------------------------------------------------------

lcd_test_pongball_crosshair lcd_block (
  .sys_clk(sys_clk_1),
  .lcd_clk(sys_clk_0),
  .sys_reset(reset),
  .lcd_reset(1'b0),
  .ball_x_enable(switch[1]),
  .ball_y_enable(switch[1]),
  .crosshair_x_pos(crosshair_x_pos),
  .crosshair_y_pos(crosshair_y_pos),
  .crosshair_color({~mouse_left,~mouse_right,1'b1}),
  .lcd_drive(lcd_drive)
  );

ps2_mouse_interface #(19660, // Watchdog timer at 400usec
                      15,    // Bits for the watchdog timer
                      186,   // Debounce timer value
                      8      // Bits for the debounce timer
                      )
  mouse1_block (             // instance name
  .clk(sys_clk_0),
  .reset(reset),
  .ps2_clk(ps2_clk[2]),
  .ps2_data(ps2_data[2]),
  .left_button(mouse_left),
  .right_button(mouse_right),
  .x_increment(x_increment),
  .y_increment(y_increment),
  .data_ready(mouse1_data_ready),   // rx_read_o
  .read(mouse1_data_ready),         // rx_read_ack_i
  .error_no_ack()
  );


//ps2_keyboard_interface #(2950, // number of clks for 60usec.
//                         12,   // number of bits needed for 60usec. timer
//                         63,   // number of clks for debounce
//                         6,    // number of bits needed for debounce timer
//                         1     // Trap the shift keys, no event generated
//                         )                       
//  keyboard1_block (            // Instance name
//  .clk(sys_clk_0),
//  .reset(reset),
//  .ps2_clk(ps2_clk[0]),
//  .ps2_data(ps2_data[0]),
//  .rx_extended(ps2_status[1]),
//  .rx_released(ps2_key_released),
//  .rx_shift_key_on(ps2_status[3]),
//  .rx_scan_code(),
//  .rx_ascii(ps2_ascii),
//  .rx_data_ready(ps2_key_data_ready),
//  .rx_read(ps2_key_data_ready),
//  .tx_data({rs232_rx_character[5],        // Make upper nibble E, F or 0
//            rs232_rx_character[5],
//            rs232_rx_character[5],
//            rs232_rx_character[4],
//            rs232_rx_character[3:0]}),
//  .tx_write(rs232_rx_data_ready),
//  .tx_write_ack_o(ps2_tx_write_ack_o),
//  .tx_error_no_keyboard_ack(ps2_status[4])
//  );
//assign ps2_status[2] = ps2_key_released;
//assign ps2_status[0] = rs232_rx_data_ready;


//// These defines are for the rs232 interface
//`define START_BITS 1
//`define DATA_BITS 8
//`define STOP_BITS 1
//`define CLOCK_FACTOR 16
//
//// This unit generates the correct 16x transmit clock (enable) frequency
//// which is used for the serial transmit operation.
//clock_gen_select clock_unit
//  (
//   .clk(sys_clk_0),
//   .reset(reset),
//   .rate_select(3'b100),         // 115,200 baud
//   .clk_out(serial_clk_16x)
//  );
//
//// A transmitter, which asserts load_request at the end of the currently
//// transmitted word.  The tx_clk must be a "clock enable" (narrow positive
//// pulse) which occurs at 16x the desired transmit rate.  If load_request
//// is connected directly to load, the unit will transmit continuously.
//rs232tx #(
//          `START_BITS,   // start_bits
//          `DATA_BITS,    // data_bits
//          `STOP_BITS,    // stop_bits (add intercharacter delay...)
//          `CLOCK_FACTOR  // clock_factor
//         )
//         rs232_tx_block // instance name
//         ( 
//          .clk(sys_clk_0),
//          .tx_clk(serial_clk_16x),
//          .reset(reset),
//          .load(   ps2_key_data_ready
//                && ps2_key_pressed
//                && rs232_tx_load_request),
//          .data(ps2_ascii),                 // Connected from keyboard
//          .load_request(rs232_tx_load_request),
//          .txd(rs232_txd)
//         );
//
//// A receiver, which asserts "word_ready" to indicate a received word.
//// Asserting "read_word" will cause "word_ready" to go low again if it was high.
//// The character is held in the output register, during the time the next
////   character is coming in.
//rs232rx #(
//          `START_BITS,  // start_bits
//          `DATA_BITS,   // data_bits
//          `STOP_BITS,   // stop_bits
//          `CLOCK_FACTOR // clock_factor
//         )
//         rs232_rx_block // instance name
//         ( 
//          .clk(sys_clk_0),
//          .rx_clk(serial_clk_16x),
//          .reset(reset || (| rs232_rx_error) ),
//          .rxd(rs232_rxd),
//          .read(ps2_tx_write_ack_o),
//          .data(rs232_rx_character),
//          .data_ready(rs232_rx_data_ready),
//          .error_over_run(rs232_rx_error[0]),
//          .error_under_run(rs232_rx_error[1]),
//          .error_all_low(rs232_rx_error[2])
//         );
//
////`undef START_BITS 
////`undef DATA_BITS 
////`undef STOP_BITS 
////`undef CLOCK_FACTOR
//

//--------------------------------------------------------------------------
// Module code
//--------------------------------------------------------------------------

always @(posedge sys_clk_0)
begin
  if (reset) begin
    crosshair_x_pos <= 10'd80;
    crosshair_y_pos <= 10'd80;
  end
  else if (mouse1_data_ready)
  begin
    crosshair_x_pos <= crosshair_x_pos + {2{x_increment[8]},x_increment[7:0]};
    crosshair_y_pos <= crosshair_y_pos - {2{y_increment[8]},y_increment[7:0]};
  end
end


//assign ps2_status[4:0] = 0;
assign rs232_txd = rs232_rxd;

assign temp1 = switch[2]?x_increment[8:1]:y_increment[8:1];
assign temp2 = {~ps2_clk,~ps2_data};
assign led = switch[3]?temp2:temp1;



endmodule