——來自迪文開發者論壇

本期為大家推送一個很有創意的迪文開發者論壇獲獎開源案例——瀏覽器網頁與T5L迪文屏串口深度擴展（Node-RED技術）。工程師使用T5L智能屏，通過Node-RED技術，只需要一個串口，就可以接入互聯網，實現迪文屏與瀏覽器網頁的數據交互。該方案實現了智能屏與網頁端的數據收發、圖表交互、基本信息顯示等功能。

Node-RED網頁端運行效果展示 （1）使用Node-RED技術，以瀏覽器作為交互入口，使瀏覽器與屏幕通過串口交互，實現相應功能展示。

數據收發Tab頁面

圖標交互Tab頁面

基本信息Tab頁面效果

（2）Node-RED網頁端主要參考代碼如下：

{

"id": "fbb314a16ea00889",

"type": "serial in",

"z": "09e0777eaff7fdea",

"g": "c1661722c7db00f9",

"name": "串口接受數據",

"serial": "83fb45b5f4b51d61",

"x": 390,

"y": 140,

"wires": [

[

"685a2fb2c2dc8fba"

]

]

},

{

"id": "1ba3c6e812e03e27",

"type": "serial out",

"z": "09e0777eaff7fdea",

"g": "c1661722c7db00f9",

"name": "串口發送",

"serial": "83fb45b5f4b51d61",

"x": 860,

"y": 260,

"wires": []

},

{

"id": "5fb7f1d3d7425133",

"type": "status",

"z": "09e0777eaff7fdea",

"g": "c1661722c7db00f9",

"name": "監聽串口狀態",

"scope": [

"fbb314a16ea00889"

],

"x": 390,

"y": 200,

"wires": [

[

"3f18d1fdea398d35"

]

]

},

{

"id": "3f18d1fdea398d35",

"type": "function",

"z": "09e0777eaff7fdea",

"g": "c1661722c7db00f9",

"name": "提取串口狀態",

"func": "let sta = msg.status.text;\nlet color = 'red';\nif (sta.indexOf('not-connected') >= 0) \n sta = '未連接';\nelse if (sta.indexOf('connected') >= 0)\n{\n sta = '連接成功';\n color = 'green';\n}else\n sta = '出現錯誤';\nmsg['payload'] = sta;\nmsg['color'] = color;\n\nreturn msg;",

"outputs": 1,

"timeout": 0,

"noerr": 0,

"initialize": "",

"finalize": "",

"libs": [],

"x": 620,

"y": 200,

"wires": [

[

"2ec78ff0b0b9a56f"

]

]

},

{

"id": "2ec78ff0b0b9a56f",

"type": "ui_template",

"z": "09e0777eaff7fdea",

"g": "c1661722c7db00f9",

"group": "4e4db779a7b91019",

"name": "顯示串口狀態",

"order": 1,

"width": 0,

"height": 0,

"format": "

\n 串口狀態:

DGUS界面設計 C51工程設計

方案采用T5L智能屏串口2與Node-RED網頁通信，部分參考代碼如下:

#include "sys.h"

#include "uart2.h"

#include

#include

u8 buff[200];

void main(void)

{

u16num;

u16val;

u16old;

u8i;

sys_init();

uart2_init(115200);

old= 0;

while(1)

{

if(is_recv_complete)

{

uart2_buf[recv_len++]= 0;

uart2_buf[recv_len++]= 0;

if(strstr((char*)uart2_buf,"cmd"))

{

num= uart2_buf[3]-'0';

if(num<3)

{

for(i=0;i<3;i++)

{

val= (num==i);

sys_write_vp(0x2300+i,(u8*)&val, 1);

}

}elseif(num<5)

{

val= (num==3);

sys_write_vp(0x2200,(u8*)&val, 1);

}

}else

{

sys_write_vp(0x2000,uart2_buf, recv_len/2+2);

}

recv_len= 0;

is_recv_complete= 0;

}

sys_read_vp(0x1000,(u8*)&val, 1);

if(val==1)

{

sys_read_vp(0x2100,buff, 50);

for(i=0;i<100;i++)

{

if(buff==0xff)

{

buff= 0x00;

buff[i+1]= 0x00;

break;

}

}

u2_send_bytes(buff,strlen(buff));

val= 0;

sys_write_vp(0x1000,(u8*)&val, 1);

}

sys_read_vp(0x2400,(u8*)&val, 1);

if(val!=old)

{

sprintf(buff,"%d", val);

u2_send_bytes(buff,strlen(buff));

old= val;

}

}

}