小梅哥AC620开发板NIOS II LWIP实现HTTP网页控制数码管的显示内容
Quartus II 13.0工程下载地址：https://pan.baidu.com/s/1_Vg6WjFp4GcsjzssqoEKCA（提取码：vtue）
【程序运行效果】
浏览器访问板子首页（http://板子IP地址/），里面有一个文本框，输入一个数字后点击确定按钮，输入的数字会显示到板子的数码管上。
网页中的文本框是数字类型（type="number"），因此在Firefox浏览器和Opera浏览器下，文本框右边会显示上下拨动的按钮，而且输入小数，输入负数，或者大于99999999的数都会提示错误，无法提交表单。
【程序说明】
Web服务器采用的是lwip自带的httpd服务器，网页表单提交方式为GET。
在lwipopts.h里面开启LWIP_HTTPD_CGI选项，可解析URL中“?”后面的参数内容，并在cgi_handler函数中使用。
开启LWIP_HTTPD_SSI选项，可将C语言变量的值动态显示到网页中，替换占位符。占位符的名称由ssi_tags字符串数组决定，替换的内容由ssi_handler函数决定。LWIP_HTTPD_SSI_INCLUDE_TAG=0表示不在网页中保留占位符。
板子上的数码管由74HC595芯片三线驱动，驱动程序由SegmentDisplay.v实现。输入的segdisp_num为BCD码，每个数位占4位，8个数位共32位。
输入数值转换成BCD码的任务由C语言完成，转换完毕后是一个uint32_t的32位数值，通过NIOS里面的PIO传入Verilog程序。
【主要C程序代码】
lwipopts.h关于HTTP的选项：
// 配置HTTP服务器
#define HTTPD_FSDATA_FILE "fsdata_custom.h"
#define LWIP_HTTPD_CGI 1
#define LWIP_HTTPD_SSI 1
#define LWIP_HTTPD_SSI_INCLUDE_TAG 0hello_world.c：
/*
* "Hello World" example.
*
* This example prints 'Hello from Nios II' to the STDOUT stream. It runs on
* the Nios II 'standard', 'full_featured', 'fast', and 'low_cost' example
* designs. It runs with or without the MicroC/OS-II RTOS and requires a STDOUT
* device in your system's hardware.
* The memory footprint of this hosted application is ~69 kbytes by default
* using the standard reference design.
*
* For a reduced footprint version of this template, and an explanation of how
* to reduce the memory footprint for a given application, see the
* "small_hello_world" template.
*
*/
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
static const char *ssi_tags[] = {"segdisp"};
static struct netif netif_rtl8201cp;
static tCGI cgis[2];
alt_u32 sys_now(void)
{
// BSP Editor里面Settings -> Common -> hal -> sys_clk_timer必须选择一个定时器
// 而且该定时器的计时间隔必须为1ms
LWIP_ASSERT("incorrect tick rate", alt_ticks_per_second() == 1000);
return alt_nticks();
}
static void display_ip(void)
{
const ip_addr_t *addr;
static uint8_t ip_displayed = 0;
static uint8_t ip6_displayed = 0;
int i, ip_present;
int dns = 0;
if (netif_dhcp_data(&netif_rtl8201cp) == NULL)
ip_present = 1; // 使用静态IP地址
else if (dhcp_supplied_address(&netif_rtl8201cp))
ip_present = 2; // 使用DHCP获得IP地址, 且已成功获取到IP地址
else
ip_present = 0; // 使用DHCP获得IP地址, 且还没有获取到IP地址
// 显示IPv4地址
if (ip_present)
{
if (ip_displayed == 0)
{
ip_displayed = 1;
if (ip_present == 2)
printf("DHCP supplied address!\r\n");
printf("IP address: %s\r\n", ipaddr_ntoa(&netif_rtl8201cp.ip_addr));
printf("Subnet mask: %s\r\n", ipaddr_ntoa(&netif_rtl8201cp.netmask));
printf("Default gateway: %s\r\n", ipaddr_ntoa(&netif_rtl8201cp.gw));
dns = 1;
}
}
else
ip_displayed = 0;
// 显示IPv6地址
for (i = 1; i < LWIP_IPV6_NUM_ADDRESSES; i++) // 0号地址是本地链路地址, 不需要显示
{
if (ip6_addr_isvalid(netif_ip6_addr_state(&netif_rtl8201cp, i)))
{
if ((ip6_displayed & _BV(i)) == 0)
{
ip6_displayed |= _BV(i);
printf("IPv6 address %d: %s\r\n", i, ipaddr_ntoa(netif_ip_addr6(&netif_rtl8201cp, i)));
dns = 1;
}
}
else
ip6_displayed &= ~_BV(i);
}
// 显示DNS服务器地址
// 在lwip中, IPv4 DHCP和IPv6 SLAAC获取到的DNS地址会互相覆盖
if (dns)
{
addr = dns_getserver(0);
if (ip_addr_isany(addr))
return;
printf("DNS Server: %s", ipaddr_ntoa(addr));
addr = dns_getserver(1);
if (!ip_addr_isany(addr))
printf(" %s", ipaddr_ntoa(addr));
printf("\r\n");
}
}
static void net_config(int use_dhcp)
{
ip4_addr_t ipaddr, netmask, gw;
if (use_dhcp)
netif_add_noaddr(&netif_rtl8201cp, NULL, ethernetif_init, netif_input);
else
{
IP4_ADDR(&ipaddr, 192, 168, 0, 19);
IP4_ADDR(&netmask, 255, 255, 255, 0);
IP4_ADDR(&gw, 192, 168, 0, 1);
netif_add(&netif_rtl8201cp, &ipaddr, &netmask, &gw, NULL, ethernetif_init, netif_input);
}
netif_set_default(&netif_rtl8201cp);
netif_set_up(&netif_rtl8201cp);
if (use_dhcp)
dhcp_start(&netif_rtl8201cp);
netif_create_ip6_linklocal_address(&netif_rtl8201cp, 1);
printf("IPv6 link-local address: %s\r\n", ipaddr_ntoa(netif_ip_addr6(&netif_rtl8201cp, 0)));
netif_set_ip6_autoconfig_enabled(&netif_rtl8201cp, 1);
}
static const char *cgi_handler(int iIndex, int iNumParams, char *pcParam[], char *pcValue[])
{
int i, num, ret;
int found = 0;
uint32_t output = 0;
for (i = 0; i < iNumParams; i++)
{
if (strcasecmp(pcParam[i], "num") == 0)
{
ret = sscanf(pcValue[i], "%d", &num);
if (ret == 1 && num >= 0 && num <= 99999999)
found = 1;
break;
}
}
if (found)
{
for (i = 0; i < 8; i++)
{
output |= (num % 10) << (4 * i);
num /= 10;
}
printf("output=0x%08lx\r\n", output);
IOWR_ALTERA_AVALON_PIO_DATA(PIO_0_BASE, output);
}
return "/index.ssi";
}
static u16_t ssi_handler(int iIndex, char *pcInsert, int iInsertLen)
{
int len;
if (iIndex == 0)
{
len = snprintf(pcInsert, iInsertLen, "%x", IORD_ALTERA_AVALON_PIO_DATA(PIO_0_BASE));
return len;
}
else
return HTTPD_SSI_TAG_UNKNOWN;
}
int main(void)
{
printf("Hello from Nios II!\r\n");
lwip_init();
net_config(1);
httpd_init();
cgis[0].pcCGIName = "/";
cgis[0].pfnCGIHandler = cgi_handler;
cgis[1].pcCGIName = "/index.ssi";
cgis[1].pfnCGIHandler = cgi_handler;
http_set_cgi_handlers(cgis, LWIP_ARRAYSIZE(cgis));
http_set_ssi_handler(ssi_handler, ssi_tags, LWIP_ARRAYSIZE(ssi_tags));
netbiosns_init();
netbiosns_set_name("EP4CE10F17C8");
while (1)
{
ethernetif_check_link(&netif_rtl8201cp);
display_ip();
ethernetif_input(&netif_rtl8201cp);
sys_check_timeouts();
}
}
lwip-2.1.2/apps/http/fs/index.ssi：（HTML5）
*.html文件为静态网页文件，*.ssi文件为动态网页文件。
8位数码管
8位数码管
这里顺便提一下Win7 IE11浏览器的一个bug：文本框输入中文后，文本框的位置会自动往下偏移1个像素，删除中文，又会往上偏移回来。
解决办法见https://blog.csdn.net/ZLK1214/article/details/80367086。
【Verilog程序代码】
main.v：
module main(
input clock,
input uart_rx,
output uart_tx,
output sdram_clk,
output [11:0] sdram_addr,
output [1:0] sdram_ba,
output sdram_cas_n,
output sdram_cke,
output sdram_cs_n,
inout [15:0] sdram_dq,
output [1:0] sdram_dqm,
output sdram_ras_n,
output sdram_we_n,
output eth_rst_n,
output eth_mdc,
inout eth_mdio,
input eth_col,
input eth_crs,
input eth_tx_clk,
output eth_tx_en,
output [3:0] eth_txd,
input eth_rx_clk,
input eth_rx_dv,
input [3:0] eth_rxd,
input eth_rx_er,
output seg_sclk,
output seg_rclk,
output seg_dio
);
/* 产生复位信号 */
wire nrst;
Reset reset(clock, nrst);
/* PLL倍频 */
wire altpll_c0;
wire altpll_locked;
altpll_0 altpll_0(
.areset(~nrst),
.inclk0(clock),
.c0(altpll_c0), // 频率等于clock, 但相位相差63度, 供SDRAM使用
.locked(altpll_locked)
);
/* 数码管 */
wire segdisp_clk;
wire [31:0] segdisp_num;
ClockDivider #(500) segdisp_divider(clock, nrst, segdisp_clk); // 50MHz/(2*500)=50kHz
SegmentDisplay segdisp(segdisp_clk, nrst, seg_sclk, seg_rclk, seg_dio, segdisp_num);
/* 缓冲eth_rx_clk和eth_tx_clk时钟输入信号, 避免CRC错误 */
wire eth_rx_clk_g;
wire eth_tx_clk_g;
altclkctrl_0 altclkctrl_0(
.inclk(eth_rx_clk),
.outclk(eth_rx_clk_g)
);
altclkctrl_1 altclkctrl_1(
.inclk(eth_tx_clk),
.outclk(eth_tx_clk_g)
);
/* NIOS II */
wire eth_tse_0_mac_mdio_connection_mdio_oen;
wire eth_tse_0_mac_mdio_connection_mdio_out;
wire eth_tse_0_mac_mii_connection_mii_tx_err;
wire eth_tse_0_mac_misc_connection_ff_rx_a_empty;
wire eth_tse_0_mac_misc_connection_ff_rx_a_full;
wire eth_tse_0_mac_misc_connection_ff_rx_dsav;
wire eth_tse_0_mac_misc_connection_ff_tx_a_empty;
wire eth_tse_0_mac_misc_connection_ff_tx_a_full;
wire eth_tse_0_mac_misc_connection_ff_tx_septy;
wire eth_tse_0_mac_misc_connection_magic_wakeup;
wire [17:0] eth_tse_0_mac_misc_connection_rx_err_stat;
wire [3:0] eth_tse_0_mac_misc_connection_rx_frm_type;
wire eth_tse_0_mac_misc_connection_tx_ff_uflow;
wire eth_tse_0_mac_status_connection_ena_10;
wire eth_tse_0_mac_status_connection_eth_mode;
assign sdram_clk = altpll_c0;
assign eth_mdio = (!eth_tse_0_mac_mdio_connection_mdio_oen) ? eth_tse_0_mac_mdio_connection_mdio_out : 1'bz;
assign eth_rst_n = altpll_locked;
nios nios(
.clk_clk(clock),
.reset_reset_n(altpll_locked),
.eth_tse_0_mac_mdio_connection_mdc(eth_mdc),
.eth_tse_0_mac_mdio_connection_mdio_in(eth_mdio),
.eth_tse_0_mac_mdio_connection_mdio_oen(eth_tse_0_mac_mdio_connection_mdio_oen),
.eth_tse_0_mac_mdio_connection_mdio_out(eth_tse_0_mac_mdio_connection_mdio_out),
.eth_tse_0_mac_mii_connection_mii_rx_d(eth_rxd),
.eth_tse_0_mac_mii_connection_mii_rx_dv(eth_rx_dv),
.eth_tse_0_mac_mii_connection_mii_rx_err(eth_rx_er),
.eth_tse_0_mac_mii_connection_mii_tx_d(eth_txd),
.eth_tse_0_mac_mii_connection_mii_tx_en(eth_tx_en),
.eth_tse_0_mac_mii_connection_mii_tx_err(eth_tse_0_mac_mii_connection_mii_tx_err),
.eth_tse_0_mac_misc_connection_ff_rx_a_empty(eth_tse_0_mac_misc_connection_ff_rx_a_empty),
.eth_tse_0_mac_misc_connection_ff_rx_a_full(eth_tse_0_mac_misc_connection_ff_rx_a_full),
.eth_tse_0_mac_misc_connection_ff_rx_dsav(eth_tse_0_mac_misc_connection_ff_rx_dsav),
.eth_tse_0_mac_misc_connection_ff_tx_a_empty(eth_tse_0_mac_misc_connection_ff_tx_a_empty),
.eth_tse_0_mac_misc_connection_ff_tx_a_full(eth_tse_0_mac_misc_connection_ff_tx_a_full),
.eth_tse_0_mac_misc_connection_ff_tx_crc_fwd(1'b0),
.eth_tse_0_mac_misc_connection_ff_tx_septy(eth_tse_0_mac_misc_connection_ff_tx_septy),
.eth_tse_0_mac_misc_connection_magic_sleep_n(1'b1),
.eth_tse_0_mac_misc_connection_magic_wakeup(eth_tse_0_mac_misc_connection_magic_wakeup),
.eth_tse_0_mac_misc_connection_rx_err_stat(eth_tse_0_mac_misc_connection_rx_err_stat),
.eth_tse_0_mac_misc_connection_rx_frm_type(eth_tse_0_mac_misc_connection_rx_frm_type),
.eth_tse_0_mac_misc_connection_tx_ff_uflow(eth_tse_0_mac_misc_connection_tx_ff_uflow),
.eth_tse_0_mac_misc_connection_xoff_gen(1'b0),
.eth_tse_0_mac_misc_connection_xon_gen(1'b0),
.eth_tse_0_mac_status_connection_ena_10(eth_tse_0_mac_status_connection_ena_10),
.eth_tse_0_mac_status_connection_eth_mode(eth_tse_0_mac_status_connection_eth_mode),
.eth_tse_0_mac_status_connection_set_10(1'b0),
.eth_tse_0_mac_status_connection_set_1000(1'b0),
.eth_tse_0_pcs_mac_rx_clock_connection_clk(eth_rx_clk_g),
.eth_tse_0_pcs_mac_tx_clock_connection_clk(eth_tx_clk_g),
.new_sdram_controller_0_wire_addr(sdram_addr),
.new_sdram_controller_0_wire_ba(sdram_ba),
.new_sdram_controller_0_wire_cas_n(sdram_cas_n),
.new_sdram_controller_0_wire_cke(sdram_cke),
.new_sdram_controller_0_wire_cs_n(sdram_cs_n),
.new_sdram_controller_0_wire_dq(sdram_dq),
.new_sdram_controller_0_wire_dqm(sdram_dqm),
.new_sdram_controller_0_wire_ras_n(sdram_ras_n),
.new_sdram_controller_0_wire_we_n(sdram_we_n),
.uart_0_external_connection_rxd(uart_rx),
.uart_0_external_connection_txd(uart_tx),
.pio_0_external_connection_export(segdisp_num)
);
endmodule
ClockDivider.v：
module ClockDivider #(
parameter N = 2
)(
input clk_in,
input nrst,
output reg clk_out
);
function integer clogb2(input integer depth);
for (clogb2 = 0; depth > 0; clogb2 = clogb2 + 1)
depth = depth >> 1;
endfunction
reg [clogb2(N - 1) - 1:0] counter;
always @(posedge clk_in, negedge nrst) begin
if (!nrst) begin
clk_out <= 0;
counter <= 0;
end
else if (counter == N - 1) begin
counter <= 0;
clk_out <= ~clk_out;
end
else
counter <= counter + 1'b1;
end
endmodule
Reset.v：
module Reset(
input clock,
output nrst
);
reg [3:0] counter = 4'd15;
assign nrst = (counter == 0);
always @(posedge clock) begin
if (!nrst)
counter <= counter - 1'b1;
end
endmodule
SegmentDisplay.v：
module SegmentDisplay(
input clock,
input nrst,
output seg_sclk,
output seg_rclk,
output reg seg_dio,
input [31:0] segdisp_num // 8位数字的BCD码
);
reg [3:0] bit_i; // 当前SPI位号
reg [2:0] num_i; // 当前数位
reg [31:0] num; // 显示的BCD码
reg [1:0] state;
assign seg_sclk = (state == 1) ? clock : 1'b0;
assign seg_rclk = (state == 2);
always @(negedge clock, negedge nrst) begin
if (!nrst)
state <= 0;
else begin
case (state)
0: begin
bit_i <= 0;
num_i <= 0;
num <= segdisp_num;
state <= 1;
end
1: begin
if (bit_i == 4'hf)
state <= 2;
bit_i <= bit_i + 1'b1;
end
2: begin
if (num_i != 3'd7)
state <= 1;
else
state <= 0;
num_i <= num_i + 1'b1;
end
endcase
end
end
reg [7:0] font;
always @(*) begin
// 数码管段码
case (num[{num_i, 2'b0}+:4])
0:
font = 8'hc0;
1:
font = 8'hf9;
2:
font = 8'ha4;
3:
font = 8'hb0;
4:
font = 8'h99;
5:
font = 8'h92;
6:
font = 8'h82;
7:
font = 8'hf8;
8:
font = 8'h80;
9:
font = 8'h90;
default:
font = 8'hff;
endcase
end
always @(*) begin
if (!bit_i[3])
seg_dio = font[~bit_i[2:0]]; // 段选
else
seg_dio = (num_i == ~bit_i[2:0]); // 位选
end
endmodule