FPGA数码管驱动模块
本工程实现了一个完整的 6位动态扫描数码管显示系统。
将任意 30 位二进制整数（最大约10亿）实时显示在数码管上，支持带小数点控制。
模块构成
| 模块名 | 功能描述 |
|---|---|
HC_FPGA_Demo_Top | 工程顶层模块，连接时钟、按键、串口、LED 与数码管等外设 |
smg | 数码管显示顶层模块，组合 binary2bcd + digital_tube |
binary2bcd | 使用 Shift-Add-3 算法将二进制转为 6 位 BCD 数字 |
digital_tube | 数码管扫描模块，实现段选/位选输出，支持小数点动态控制 |
顶层模块
module HC_FPGA_Demo_Top
(input CLOCK_XTAL_50MHz,input RESET,input KEY4,input SIG_IN,input RXD,output TXD,output LED0,output LED1,output LED2,output LED3,output SIG_OUT1,output SIG_OUT2,output SIG_OUT3,output SIG_OUT4,output SIG_OUT5,output[7:0] DIG,output[5:0] SEL
);parameter CLK_FREQ = 50000000; //定义系统时钟频率wire [29:0] smg_disp_data;smg u_smg (.i_clk(CLOCK_XTAL_50MHz),.i_rst_n(RESET),.i_data(123456),.i_dp(0),.o_sel(SEL),.o_seg(DIG)
);endmodule数码管显示模块
/*** 数码管显示模块* - 输入：30 位二进制数字* - 输出：6 位数码管段选与位选（带小数点）* - 结构：binary2bcd + digital_tube*/
module smg (input wire i_clk , // 时钟input wire i_rst_n , // 异步复位，低有效input wire [29:0] i_data , // 输入 30bit 二进制数据input wire [5:0] i_dp , // 小数点控制（1亮）output wire [5:0] o_sel , // 数码管位选（低有效）output wire [7:0] o_seg // 数码管段选（负逻辑）
);// ==================================================// 中间信号定义// ==================================================wire w_bcd_vld;wire [3:0] w_bcd_d0, w_bcd_d1, w_bcd_d2, w_bcd_d3, w_bcd_d4, w_bcd_d5;// ==================================================// 二进制转BCD模块（显示6位十进制）// ==================================================binary2bcd u_binary2bcd (.i_clk (i_clk),.i_rst_n (i_rst_n),.i_data (i_data),.o_data ({w_bcd_d0, w_bcd_d1, w_bcd_d2, w_bcd_d3, w_bcd_d4, w_bcd_d5}),.o_data_vld (w_bcd_vld));// ==================================================// 数码管扫描显示模块// ==================================================digital_tube #(.P_CLK_FREQ (50_000_000),.P_SCAN_FREQ (1_000),.P_DIGIT_NUM (6)) u_digital_tube (.i_clk (i_clk),.i_rst_n (i_rst_n),.i_dig0 (w_bcd_d0),.i_dig1 (w_bcd_d1),.i_dig2 (w_bcd_d2),.i_dig3 (w_bcd_d3),.i_dig4 (w_bcd_d4),.i_dig5 (w_bcd_d5),.i_dp (i_dp),.o_sel (o_sel),.o_seg (o_seg));endmodule二进制转BCD
/** 二进制转BCD* Shift-Add-3 Algorithm* 输入：i_data（二进制）* 输出：o_data（BCD），o_data_vld（完成标志）*/
module binary2bcd #(parameter P_DATA_WIDTH = 30, // 输入数据位宽parameter P_CLK_FREQ = 50_000_000 // 时钟频率（保留风格一致性）
) (input wire i_clk , // 时钟input wire i_rst_n , // 异步复位，低有效input wire [P_DATA_WIDTH-1:0] i_data , // 输入二进制数output reg [36:0] o_data , // 输出9位BCD码，共36位output reg o_data_vld // 有效标志
);// ==================================================// Local Parameters// ==================================================localparam L_CNT_SHIFT_NUM = P_DATA_WIDTH;localparam L_SHIFT_WIDTH = P_DATA_WIDTH + 36; // BCD(9位) + 二进制// ==================================================// Registers// ==================================================reg [6:0] r_cnt_shift;reg [L_SHIFT_WIDTH-1:0] r_data_shift;reg r_shift_flag;// ==================================================// 移位控制计数器// ==================================================always @(posedge i_clk or negedge i_rst_n) beginif (!i_rst_n)r_cnt_shift <= 7'd0;else if ((r_cnt_shift == L_CNT_SHIFT_NUM + 1) && r_shift_flag)r_cnt_shift <= 7'd0;else if (r_shift_flag)r_cnt_shift <= r_cnt_shift + 1'b1;end// ==================================================// BCD移位转换逻辑// ==================================================always @(posedge i_clk or negedge i_rst_n) beginif (!i_rst_n)r_data_shift <= {L_SHIFT_WIDTH{1'b0}};else if (r_cnt_shift == 0)r_data_shift <= {{36{1'b0}}, i_data};else if ((r_cnt_shift <= L_CNT_SHIFT_NUM) && !r_shift_flag) beginif (r_data_shift[65:62] > 4) r_data_shift[65:62] <= r_data_shift[65:62] + 3;if (r_data_shift[61:58] > 4) r_data_shift[61:58] <= r_data_shift[61:58] + 3;if (r_data_shift[57:54] > 4) r_data_shift[57:54] <= r_data_shift[57:54] + 3;if (r_data_shift[53:50] > 4) r_data_shift[53:50] <= r_data_shift[53:50] + 3;if (r_data_shift[49:46] > 4) r_data_shift[49:46] <= r_data_shift[49:46] + 3;if (r_data_shift[45:42] > 4) r_data_shift[45:42] <= r_data_shift[45:42] + 3;if (r_data_shift[41:38] > 4) r_data_shift[41:38] <= r_data_shift[41:38] + 3;if (r_data_shift[37:34] > 4) r_data_shift[37:34] <= r_data_shift[37:34] + 3;if (r_data_shift[33:30] > 4) r_data_shift[33:30] <= r_data_shift[33:30] + 3;end else if ((r_cnt_shift <= L_CNT_SHIFT_NUM) && r_shift_flag)r_data_shift <= r_data_shift << 1;end// ==================================================// 交替控制加3/移位// ==================================================always @(posedge i_clk or negedge i_rst_n) beginif (!i_rst_n)r_shift_flag <= 1'b0;elser_shift_flag <= ~r_shift_flag;end// ==================================================// 结果输出// ==================================================always @(posedge i_clk or negedge i_rst_n) beginif (!i_rst_n) begino_data <= 36'd0;o_data_vld <= 1'b0;end else if (r_cnt_shift == L_CNT_SHIFT_NUM + 1) begino_data <= r_data_shift[65:30]; // 取出 BCD 码部分o_data_vld <= 1'b1;end else begino_data_vld <= 1'b0;endendendmodule数码管扫描显示模块
/*** ===============================================* 数码管扫描显示模块（Digital Tube Driver）* ===============================================*/module digital_tube #(parameter P_CLK_FREQ = 50_000_000, // 输入时钟频率（Hz）parameter P_SCAN_FREQ = 1_000, // 数码管刷新频率（Hz）parameter P_DIGIT_NUM = 6 // 数码管位数
) (input wire i_clk , // 时钟信号input wire i_rst_n , // 异步复位，低有效input wire [3:0] i_dig0 , // 各位数字输入（0~F）input wire [3:0] i_dig1 ,input wire [3:0] i_dig2 ,input wire [3:0] i_dig3 ,input wire [3:0] i_dig4 ,input wire [3:0] i_dig5 ,input wire [P_DIGIT_NUM-1:0] i_dp , // 小数点控制（1亮）output reg [P_DIGIT_NUM-1:0] o_sel , // 数码管位选（低有效）output reg [7:0] o_seg // 数码管段选（低有效）
);// ==================================================// 扫描频率计数器// ==================================================localparam integer L_SCAN_CNT_MAX = P_CLK_FREQ / P_SCAN_FREQ;reg [15:0] r_scan_cnt;wire w_scan_cnt_end = (r_scan_cnt == L_SCAN_CNT_MAX - 1);always @(posedge i_clk or negedge i_rst_n) beginif (!i_rst_n)r_scan_cnt <= 0;else if (w_scan_cnt_end)r_scan_cnt <= 0;elser_scan_cnt <= r_scan_cnt + 1'b1;end// ==================================================// 位索引计数器// ==================================================reg [2:0] r_digit_idx;always @(posedge i_clk or negedge i_rst_n) beginif (!i_rst_n)r_digit_idx <= 0;else if (w_scan_cnt_end)r_digit_idx <= (r_digit_idx == P_DIGIT_NUM - 1) ? 0 : r_digit_idx + 1'b1;end// ==================================================// 数码管片选与数据选择// ==================================================reg [3:0] r_hex;reg r_dp;always @(*) begincase (r_digit_idx)3'd0: begin o_sel = 6'b111110; r_hex = i_dig0; r_dp = i_dp[0]; end3'd1: begin o_sel = 6'b111101; r_hex = i_dig1; r_dp = i_dp[1]; end3'd2: begin o_sel = 6'b111011; r_hex = i_dig2; r_dp = i_dp[2]; end3'd3: begin o_sel = 6'b110111; r_hex = i_dig3; r_dp = i_dp[3]; end3'd4: begin o_sel = 6'b101111; r_hex = i_dig4; r_dp = i_dp[4]; enddefault: begin o_sel = 6'b011111; r_hex = i_dig5; r_dp = i_dp[5]; endendcaseend// ==================================================// 数码管段码定义（负逻辑）// ==================================================localparam [7:0] L_NUM0 = ~8'h3f;localparam [7:0] L_NUM1 = ~8'h06;localparam [7:0] L_NUM2 = ~8'h5b;localparam [7:0] L_NUM3 = ~8'h4f;localparam [7:0] L_NUM4 = ~8'h66;localparam [7:0] L_NUM5 = ~8'h6d;localparam [7:0] L_NUM6 = ~8'h7d;localparam [7:0] L_NUM7 = ~8'h07;localparam [7:0] L_NUM8 = ~8'h7f;localparam [7:0] L_NUM9 = ~8'h6f;localparam [7:0] L_NUMA = ~8'h77;localparam [7:0] L_NUMB = ~8'h7c;localparam [7:0] L_NUMC = ~8'h39;localparam [7:0] L_NUMD = ~8'h5e;localparam [7:0] L_NUME = ~8'h79;localparam [7:0] L_NUMF = ~8'h71;// ==================================================// 段选译码输出// ==================================================always @(posedge i_clk or negedge i_rst_n) beginif (!i_rst_n)o_seg <= 8'hff;else begincase (r_hex)4'h0: o_seg[6:0] <= L_NUM0[6:0];4'h1: o_seg[6:0] <= L_NUM1[6:0];4'h2: o_seg[6:0] <= L_NUM2[6:0];4'h3: o_seg[6:0] <= L_NUM3[6:0];4'h4: o_seg[6:0] <= L_NUM4[6:0];4'h5: o_seg[6:0] <= L_NUM5[6:0];4'h6: o_seg[6:0] <= L_NUM6[6:0];4'h7: o_seg[6:0] <= L_NUM7[6:0];4'h8: o_seg[6:0] <= L_NUM8[6:0];4'h9: o_seg[6:0] <= L_NUM9[6:0];4'ha: o_seg[6:0] <= L_NUMA[6:0];4'hb: o_seg[6:0] <= L_NUMB[6:0];4'hc: o_seg[6:0] <= L_NUMC[6:0];4'hd: o_seg[6:0] <= L_NUMD[6:0];4'he: o_seg[6:0] <= L_NUME[6:0];4'hf: o_seg[6:0] <= L_NUMF[6:0];default: o_seg[6:0] <= 7'b0000000;endcaseo_seg[7] <= ~r_dp; // 小数点控制：高亮 = 段信号为低endendendmodule