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1、fpga设计电子时钟（12864显示）设计心得：1，进行分块设计，类似调用函数，脉冲使能2，充分了解fpga的并行特性（c程序的串行特性，不能并行处理，线性：只有完成了当前任务，才能进行下一个任务）设计问题：1，似乎读有问题，在char_LR=1时，写的数据为汉字（程序中时间没有更改，主要为了调试看波形）实际板子验证时，将LCD_clk模块中的分频调为50到100kHz左右整体架构控制时序功能模块时序处理功能模块初始化写汉字写字符绘图1，液晶上电初始化2，清屏1，采用绘图模式2，一次一个汉字3，位置，编码编号1，采用CDRAM模式2，一次一个字符3，位置1，采用绘图模式2，大小可变（库编码内存
2、不变）3，位置，长宽非忙应答液晶初始化时序parameter Idle=8b0000_0001,Basic_com=8b0000_0010,/basic instruction:0x30Disp_set=8b0000_0100,/set show curse blingDDRAM_clear=8b0000_1000,/colunm address XWait_clear=8b0001_0000,Point_set=8b0010_0000,Show_on=8b0100_0000,Stop=8b1000_0000;写字符的时序由于字符属于半宽字形，且DDRAM形式下，每行只有8个地址，而字符可以写
3、16个，因此用下面三个来表示写的地址：input 1:0 Y,/row 0-3input 2:0X,/clunm 0-7input LR,/0/1因此当LR=0时，直接写地址，然后写一个字符编码即可 LR=1时，先写地址，读出高位数据，然后写入两个字节（读出的数据，要写的数据）parameter Idle=8b0000_0001,DDRAM=8b0000_0010,/drawing modeW_addr=8b0000_0100,/row address YDummy=8b0000_1000,/ not really readingR_data=8b0001_0000,/reading high
4、 byte dataW0_data=8b0010_0000,W1_data=8b0100_0000,Stop=8b1000_0000;# t1: 0 t2: 2305, T: 10,n_init: 38# t1: 2305 t2: 2665, T: 10,n_char: 6# t1: 2665 t2: 3265, T: 10,n_char: 10完成了上述工作，就可以设计一个简单的电子时钟，其要求如下：在屏幕上显示时间 00：00：00要动态走（主要就是控制脉冲信号的产生）设计思路：1，按下复位键，系统复位，时间变为00：00：002，每一秒中时分秒数据更改3，一秒钟时间到，产生8个字符写的脉
5、冲，LCD更新数据显示00:00:0100:01:591代码/*sign.v/creat the control sign clock h:m:s*/module sign(/module LED(input lcd_clk,/100kHzinput sys_rst,output reg lcd_char_en,output reg lcd_init_en,output reg 7:0char_data,output reg 2:0char_X,output reg 1:0char_Y,output reg char_LR);parameter T_w_char = 5, T_lcd_init
6、 = 40;reg 47:0 time_out;/* 1s */reg 16:0 cnt_s;reg 5:0 cnt0_clk;reg 3:0 cnt1_clk;reg 2:0 cnt_char;reg 5:0 sec,min;reg 4:0 hour;reg flag_s,flag_init;always (posedge lcd_clk or negedge sys_rst)begin /100kHzif(!sys_rst)begincnt_s =0;cnt0_clk=0;cnt1_clk=0;cnt_char=0;sec =0;min =0;hour =0;flag_s =0;flag_
7、init =1b1; char_Y = 2b10; endelsebeginif(cnt_s = (40-1)begincnt_s =0;flag_s=1b1;data_deal;/taskendelsecnt_s =cnt_s+1b1;if(flag_init) begincnt0_clk = cnt0_clk +1b1;case(cnt0_clk)1: begin lcd_init_en =1b0;end2: begin lcd_init_en =1b1;end3: begin lcd_init_en =1b1;end4: begin lcd_init_en =1b0;endT_lcd_i
8、nit: begin flag_init =0;cnt0_clk =0;enddefault: lcd_init_en =0;endcase endelseif(flag_s)begincnt1_clk = cnt1_clk +1b1;case(cnt1_clk)1: begin lcd_char_en =1b0;end2: begin lcd_char_en =1b1;end3: begin lcd_char_en =1b1;end4: begin lcd_char_en =1b0;endT_w_char: begin if(cnt_char = 3b111)begin cnt_char=0
9、; flag_s =0; endelsecnt_char =cnt_char+1b1;cnt1_clk =0;enddefault: lcd_char_en =0;endcasecase(cnt_char)/2 3 4 50: begin char_X =3b000; char_LR =0; char_data =time_out47:40; end/x0:00:001: begin char_X =3b001; char_LR =0; char_data =time_out39:32; end /0x:00:002: begin char_X =3b010; char_LR =0; char
10、_data =8h3a; end /: ascii 0583: begin char_X =3b011; char_LR =0; char_data =time_out31:24; end /00:x0:004: begin char_X =3b100; char_LR =0; char_data =time_out23:16; end /00:0x:005: begin char_X =3b101; char_LR =0; char_data =8h3a; end /: ascii 0586: begin char_X =3b110; char_LR =0; char_data =time_
11、out15: 8; end /00:00:x07: begin char_X =3b111; char_LR =0; char_data =time_out7 : 0; endendcaseendendendtask data_deal;beginif(sec = 59)if(min =59) if(hour = 23)beginhour=0;min=0;sec=0; endelsebegin hour=hour + 1b1; min =0; sec=0; endelsebegin min = min+1b1; sec =0; endelsesec = sec +1b1;time_out47:
12、40 = 8h30+(hour/10);time_out39:32 = 8h30+(hour%10);time_out31:24 = 8h30+(min /10);time_out23:16 = 8h30+(min %10);time_out15: 8 = 8h30+(sec /10);time_out 7: 0 = 8h30+(sec %10);endendtaskendmodule2代码module LCD_init(/module LED(input lcd_clk,input sys_clk,input lcd_en,/1 is activedoutput regLCD_RS,outp
13、utregLCD_RW,output regLCD_EN,inout 7:0 LCD_DATA,output regACK);reg flag;reg 7:0 lcd_data;reg 7:0State;reg link_rs;reg link_data;parameter Idle=8b0000_0001,Basic_com=8b0000_0010,/basic instruction:0x30Disp_set=8b0000_0100,/set show curse blingDDRAM_clear=8b0000_1000,/colunm address XWait_clear=8b0001
14、_0000,Point_set=8b0010_0000,Show_on=8b0100_0000,Stop=8b1000_0000;reg 9:0cnt;/16*2*32=210 byte(8bits)/* LCD_RW LCD_DATA*/assign LCD_DATA = link_data ? lcd_data: 8hzz;/* LCD_RW LCD_EN */always (posedge sys_clk) beginif(flag)beginLCD_RW =0;LCD_EN = lcd_clk;endelsebeginLCD_RW =1bz;LCD_EN =1bz;endend/* L
15、CD_RS */always (posedge lcd_clk) beginif(link_rs)LCD_RS =1b0;elseLCD_RS =1bz;end/*-Main state transter-*/always (posedge lcd_clk) begincase (State)Idle: beginif(lcd_en)begin link_rs=1; State= Basic_com; endelseState= Idle; ACK =0; flag=1b0;lcd_data= 8hzz;cnt= 0;endBasic_com: beginflag=1b1;link_data
16、=1b1;cnt = cnt +1b1;if(cnt = 1)State= Disp_set;elseState= Basic_com;lcd_data= 8h30;endDisp_set: beginState= DDRAM_clear;lcd_data= 8h0c;/show curse blink is offendDDRAM_clear: beginState= Wait_clear;lcd_data= 8h01;endWait_clear: begincnt =cnt +1b1;link_data = 1b0;flag =0;lcd_data= 8hzz;if(cnt = 30)St
17、ate = Point_set;elseState = Wait_clear;endPoint_set: begin flag =1b1; link_data =1b1;State= Show_on;lcd_data= 8h06;/point +1 automatically,screen move offendShow_on: beginState= Stop;lcd_data= 8h0c;endStop: beginState= Idle;flag=1b0;link_data =1b0;ACK=1b1;lcd_data= 8hzz;cnt= 0;link_rs =0;enddefault:
18、begin ACK =0;State = Idle;endendcaseendendmodule3代码/module LCD_top(module LED(input sys_clk,input sys_rst,output LCD_RS,output LCD_RW,output LCD_EN,inout 7:0LCD_DATA,output BUSY);wire 7:0 char_data;wire 2:0 char_X;wire 1:0 char_Y;sign singb(.lcd_clk(lcd_clk),/100kHz.sys_rst(sys_rst),.lcd_char_en(lcd
19、_char_en),.lcd_init_en(lcd_init_en),.char_data(char_data),.char_X(char_X),.char_Y(char_Y),.char_LR(char_LR);LCD_init lcd_init(.lcd_clk(lcd_clk),.sys_clk(sys_clk),.lcd_en(lcd_init_en),/1 is actived.LCD_RS(LCD_RS),.LCD_RW(LCD_RW),.LCD_EN(LCD_EN),.LCD_DATA(LCD_DATA),.ACK(init_ack);LCD_charac a(.lcd_clk
20、(lcd_clk),.sys_clk(sys_clk),.lcd_en(lcd_char_en),/1 is actived.Y(char_Y),/row 0-3.X(char_X),/clunm 0-7.LR(char_LR),/0/1.data_disp(char_data),.LCD_RS(LCD_RS),.LCD_RW(LCD_RW),.LCD_EN(LCD_EN),.LCD_DATA(LCD_DATA),.ACK(init_ack);LCD_clk clk1(.sys_clk(sys_clk),.lcd_clk(lcd_clk);endmodule4代码module LCD_clk(
21、/module LED(input sys_clk,output reg lcd_clk);/*-creat the 25kHz clock-*/reg 11:0 lcd_cnt;always (posedge sys_clk) beginif(lcd_cnt = 2)/100kHzbeginlcd_cnt =0;lcd_clk = lcd_clk;endelselcd_cnt = lcd_cnt +1b1;endinitial begin lcd_clk =0; lcd_cnt =0; endendmodule5代码/* to display character */module LCD_c
22、harac(/module LED(input lcd_clk,input sys_clk,input lcd_en,/1 is activedinput 1:0 Y,/row 0-3input 2:0 X,/clunm 0-7input LR,/0/1input 7:0 data_disp,output reg LCD_RS,output reg LCD_RW,output reg LCD_EN,inout 7:0 LCD_DATA,output regACK);reg 7:0 lcd_data;reg 7:0R_buff;reg 7:0State;parameter Idle=8b0000
23、_0001,DDRAM=8b0000_0010,/drawing modeW_addr=8b0000_0100,/row address YDummy=8b0000_1000,/ not really readingR_data=8b0001_0000,/reading high byte dataW0_data=8b0010_0000,W1_data=8b0100_0000,Stop=8b1000_0000;reg flag,cnt;reg link_data;reg flag0;/* LCD_DATA */assign LCD_DATA = link_data ? lcd_data :8h
24、zz;/* LCD_EN */always (posedge sys_clk) beginif(flag = 1b1)LCD_EN = lcd_clk;elseLCD_EN =1bz;end/* LCD_RW */always (posedge lcd_clk) beginif(flag0)if(State = Dummy | State = R_data)LCD_RW =1b1;elseLCD_RW =1b0;elseLCD_RW =1bz;end/* LCD_RS */always (posedge lcd_clk) beginif(flag0)if(State = W0_data | S
25、tate = W1_data | State = Dummy | State = R_data)LCD_RS =1b1;elseLCD_RS =1b0;elseLCD_RS =1bz;end/*-Main state transter-*/always (posedge lcd_clk) begincase (State)Idle: beginif(lcd_en)begin State= DDRAM; link_data =1; flag0=1b1; endelsebegin State= Idle; flag0= 1b0;endflag= 1b0;lcd_data= 8hzz;ACK =0;
26、endDDRAM: begin/here flag is changed,not Idle, cause sys_clkflag= 1b1;State= W_addr;link_data =1;lcd_data = 8h30;endW_addr: begin if(!cnt) begin if(LR) State= Dummy; else State= W0_data; cnt =1b1; endelse State = W0_data;case (Y)2b00: lcd_data = 8h80 + X;2b01: lcd_data = 8h90 + X;2b10: lcd_data = 8h
27、88 + X;2b11: lcd_data = 8h98 + X;endcaselink_data =1b1;endDummy: beginState= R_data;R_buff= LCD_DATA;link_data =0;endR_data: beginState=W_addr; R_buff= LCD_DATA;endW0_data: beginif( !LR) beginlcd_data= data_disp;State= Stop;endelsebeginlcd_data= R_buff;State= W1_data;endendW1_data : beginlcd_data= data_disp;State =Stop;flag0=0;endStop: begin State= Idle;flag= 1b0;lcd_data= 8hzz;cnt= 0;ACK= 1;enddefault:begin ACK =0;State = Idle; link_data=0 ;endendcaseendendmodule
