PS2键盘编码Verilog源程序

除了顶层模块，三个底层模块分别为PS/2传输处理模块、串口传输模块以及串口波特率选择模块（下面只给出顶层模块和PS/2传输处理模块的Verilog代码）。 Module Ps2_key(Clk,Rst_n,Ps2k_clk,Ps2k_data,Rs232_tx); Input Clk; //50M时钟信号 Input Rst_n; //复位信号 Input Ps2k_clk; //PS2接口时钟信号 Input Ps2k_data; //PS2接口数据信号 Output Rs232_tx; // RS232发送数据信号 Wire[7:0] Ps2_byte; // 1byte键值 Wire Ps2_state; //按键状态标志位 Wire Bps_start; //接收到数据后，波特率时钟启动信号置位 Wire Clk_bps; // Clk_bps的高电平为接收或者发送数据位的中间采样点  Ps2scan Ps2scan( .Clk(Clk), //按键扫描模块 .Rst_n(Rst_n),  .Ps2k_clk(Ps2k_clk), .Ps2k_data(Ps2k_data), .Ps2_byte(Ps2_byte), .Ps2_state(Ps2_state) );  Speed_select Speed_select( .Clk(Clk), .Rst_n(Rst_n), .Bps_start(Bps_start), .Clk_bps(Clk_bps) ); My_uart_tx My_uart_tx( .Clk(Clk), .Rst_n(Rst_n), .Clk_bps(Clk_bps), .Rx_data(Ps2_byte), .Rx_int(Ps2_state), .Rs232_tx(Rs232_tx), .Bps_start(Bps_start) );  Endmodule  Module Ps2scan(Clk,Rst_n,Ps2k_clk,Ps2k_data,Ps2_byte,Ps2_state); Input Clk; //50M时钟信号 Input Rst_n; //复位信号 Input Ps2k_clk; //PS2接口时钟信号 Input Ps2k_data; //PS2接口数据信号 Output[7:0] Ps2_byte; // 1byte键值，只做简单的按键扫描 Output Ps2_state; //键盘当前状态，Ps2_state=1表示有键被按下  //------------------------------------------ Reg Ps2k_clk_r0,Ps2k_clk_r1,Ps2k_clk_r2; //Ps2k_clk状态寄存器 //Wire Pos_ps2k_clk; // Ps2k_clk上升沿标志位 Wire Neg_ps2k_clk; // Ps2k_clk下降沿标志位 Always @ (Posedge Clk Or Negedge Rst_n) Begin If(!Rst_n) Begin Ps2k_clk_r0 <= 1''B0; Ps2k_clk_r1 <= 1''B0; Ps2k_clk_r2 <= 1''B0; End Else Begin //锁存状态，进行滤波 Ps2k_clk_r0 <= Ps2k_clk; Ps2k_clk_r1 <= Ps2k_clk_r0; Ps2k_clk_r2 <= Ps2k_clk_r1; End End Assign Neg_ps2k_clk = ~Ps2k_clk_r1 & Ps2k_clk_r2; //下降沿 //------------------------------------------ Reg[7:0] Ps2_byte_r; //PC接收来自PS2的一个字节数据存储器 Reg[7:0] Temp_data; //当前接收数据寄存器 Reg[3:0] Num; //计数寄存器 Always @ (Posedge Clk Or Negedge Rst_n) Begin If(!Rst_n) Begin Num <= 4''D0; Temp_data <= 8''D0; End Else If(Neg_ps2k_clk) Begin //检测到Ps2k_clk的下降沿Case (Num) 4''D0: Num <= Num+1''B1; 4''D1: Begin Num <= Num+1''B1; Temp_data[0] <= Ps2k_data; //Bit0 End 4''D2: Begin Num <= Num+1''B1; Temp_data[1] <= Ps2k_data; //Bit1 End 4''D3: Begin Num <= Num+1''B1; Temp_data[2] <= Ps2k_data; //Bit2 End 4''D4: Begin Num <= Num+1''B1; Temp_data[3] <= Ps2k_data; //Bit3 End 4''D5: Begin Num <= Num+1''B1; Temp_data[4] <= Ps2k_data; //Bit4 End 4''D6: Begin Num <= Num+1''B1; Temp_data[5] <= Ps2k_data; //Bit5 End 4''D7: Begin Num <= Num+1''B1; Temp_data[6] <= Ps2k_data; //Bit6 End 4''D8: Begin Num <= Num+1''B1; Temp_data[7] <= Ps2k_data; //Bit7 End 4''D9: Begin Num <= Num+1''B1; //奇偶校验位，不做处理 End 4''D10: Begin Num <= 4''D0; // Num清零 End Default: ; Endcase End  End Reg Key_f0; //松键标志位，置1表示接收到数据8''Hf0，再接收到下一个数据后清零 Reg Ps2_state_r; //键盘当前状态，Ps2_state_r=1表示有键被按下  Always @ (Posedge Clk Or Negedge Rst_n) Begin //接收数据的相应处理，这里只对1byte的键值进行处理 If(!Rst_n) Begin Key_f0 <= 1''B0; Ps2_state_r <= 1''B0; End Else If(Num==4''D10) Begin //刚传送完一个字节数据 If(Temp_data == 8''Hf0) Key_f0 <= 1''B1; Else Begin If(!Key_f0) Begin //说明有键按下 Ps2_state_r <= 1''B1; Ps2_byte_r <= Temp_data; //锁存当前键值 End Else Begin Ps2_state_r <= 1''B0; Key_f0 <= 1''B0; End End End End Reg[7:0] Ps2_asci; //接收数据的相应ASCII码 Always @ (Ps2_byte_r) Begin Case (Ps2_byte_r) //键值转换为ASCII码，这里做的比较简单，只处理字母 8''H15: Ps2_asci <= 8''H51; //Q 8''H1d: Ps2_asci <= 8''H57; //W 8''H24: Ps2_asci <= 8''H45; //E 8''H2d: Ps2_asci <= 8''H52; //R 8''H2c: Ps2_asci <= 8''H54; //T 8''H35: Ps2_asci <= 8''H59; //Y 8''H3c: Ps2_asci <= 8''H55; //U 8''H43: Ps2_asci <= 8''H49; //I 8''H44: Ps2_asci <= 8''H4f; //O 8''H4d: Ps2_asci <= 8''H50; //P  8''H1c: Ps2_asci <= 8''H41; //A 8''H1b: Ps2_asci <= 8''H53; //S 8''H23: Ps2_asci <= 8''H44; //D 8''H2b: Ps2_asci <= 8''H46; //F 8''H34: Ps2_asci <= 8''H47; //G 8''H33: Ps2_asci <= 8''H48; //H 8''H3b: Ps2_asci <= 8''H4a; //J 8''H42: Ps2_asci <= 8''H4b; //K 8''H4b: Ps2_asci <= 8''H4c; //L 8''H1z: Ps2_asci <= 8''H5a; //Z 8''H22: Ps2_asci <= 8''H58; //X 8''H21: Ps2_asci <= 8''H43; //C 8''H2a: Ps2_asci <= 8''H56; //V 8''H32: Ps2_asci <= 8''H42; //B 8''H31: Ps2_asci <= 8''H4e; //N 8''H3a: Ps2_asci <= 8''H4d; //M Default: ;