【快速入门教程】EG系列边缘计算网关Node-RED零代码编程08—

【快速入门教程】EG系列边缘计算网关Node-RED零代码编程08——DI&DO节点

2024-07-03 11:12:09 阅读：发布人：纵横智控

大家好，我们继续学习EG系列边缘计算网关的Node-RED可视化编程，今天要讲解的是【DI&DO节点】。 EG网关自带若干个DI/DO节点，DI（数字输入）和DO（数字输出）节点通常用于与各种硬件设备进行交互，如传感器、执行器等，下面让我们一起来学习吧！

DI（数字输入）节点

【DI节点】

当DI节点检测到DI接口的信号有变化时，会主动输出1/0来表示当前DI接口的状态。其中1表示DI检测到高电平，0表示DI检测到低电平。

PS：该节点支持检测NPN(包括干接点)和PNP。默认支持NPN模式，如需要PNP，请在采购时向客服说明。

边缘计算网关/物联网平台/网关模块/纵横智控

【DI节点】功能

1. 定时刷新状态

DI节点会根据设置的时间，周期性的刷新当前的DI状态。存储在全局变量“DI_X”中，X为DI的通道号。当然，即使不设置定时刷新，DI如果发生状态变化也会主动更新“DI_X”。

2. 全局变量

在函数计算如果需要获DI的当前状态，可以使用以下语法获取：

global.get("DI_1")
#注意1:流程内至少存在一个开关量输入节点，才会使能开关量输入的全局变量，才能读取
#注意2:如果已经初始化了全局变量，重启网关才能删除全局变量

全局变量可以很直观的在右侧全局变量窗口查看：

边缘计算网关/物联网平台/网关模块/纵横智控

【DI节点】实操步骤

手动改变DI1口接近开关传感器的状态，观察结果。同时通过函数计算节点读取全局变量：

边缘计算网关/物联网平台/网关模块/纵横智控

所有的流程支持以json格式导入导出，方便与其他人分享做好的流程。本节的流程json文件如下，复制后在菜单栏右上角选择导入粘贴即可，导出同理：

[{"id":"1f3f938edf2e8c81","type":"function","z":"2ff624305b8cb30b","name":"函数计算 1","func":"msg.payload = global.get(\"DO_1\")\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":390,"y":340,"wires":[["6e804d72c4c1c473"]]},{"id":"b416ef03a7d8eb0d","type":"inject","z":"2ff624305b8cb30b","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":210,"y":340,"wires":[["1f3f938edf2e8c81"]]},{"id":"6e804d72c4c1c473","type":"debug","z":"2ff624305b8cb30b","name":"调试 2","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":550,"y":340,"wires":[]},{"id":"f25caf631b7b0f87","type":"di","z":"2ff624305b8cb30b","name":"","index":"1","interval":false,"intervalValue":1000,"x":250,"y":220,"wires":[["6ee35db5424a4d26"]]},{"id":"6ee35db5424a4d26","type":"debug","z":"2ff624305b8cb30b","name":"调试 1","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":470,"y":220,"wires":[]}]

DO（数字输出）节点

【DO节点】

可以通过对【DO节点】写入1/0或者true/false来实现控制继电器的吸合或者断开。

继电器容量：10A/250VAC 30VDC，即最大可直接承载2500W的用电设备。一般接大功率用电设备时，建议加接触器或者中间继电器进行强弱电隔离。

边缘计算网关/物联网平台/网关模块/纵横智控

【DO节点】功能

1. 定时刷新状态

DO节点会根据设置的时间，周期性的刷新当前的继电器状态。存储在全局变量“DO_X”中，X为继电器的通道号。

2. 全局变量

在函数计算如果需要获取继电器的当前状态，可以使用以下语法获取：

global.get("DO_1")
#注意1:流程内至少存在一个继电器节点，才会使能继电器的全局变量，才能读取
#注意2:如果已经初始化了全局变量，重启网关才能删除全局变量

全局变量可以很直观的在右侧全局变量窗口查看：

边缘计算网关/物联网平台/网关模块/纵横智控

【DO节点】实操步骤：

1. 控制继电器&获取继电器状态

函数计算读取DO_1即第一路继电器的状态，赋值给msg.payload后通过调试2打印在日志窗口：

边缘计算网关/物联网平台/网关模块/纵横智控

json文件：

[{"id":"2dafde0160e2ba6b","type":"do","z":"2ff624305b8cb30b","name":"","index":"1","interval":false,"intervalValue":1000,"x":410,"y":180,"wires":[["a603591f3e178be1"]]},{"id":"6992c0ad230b940b","type":"inject","z":"2ff624305b8cb30b","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"true","payloadType":"bool","x":230,"y":160,"wires":[["2dafde0160e2ba6b"]]},{"id":"a603591f3e178be1","type":"debug","z":"2ff624305b8cb30b","name":"调试 1","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":570,"y":180,"wires":[]},{"id":"149a0ab24f4c5d8c","type":"inject","z":"2ff624305b8cb30b","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"false","payloadType":"bool","x":230,"y":200,"wires":[["2dafde0160e2ba6b"]]},{"id":"1f3f938edf2e8c81","type":"function","z":"2ff624305b8cb30b","name":"函数计算 1","func":"msg.payload = global.get(\"DO_1\")\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":410,"y":300,"wires":[["6e804d72c4c1c473"]]},{"id":"b416ef03a7d8eb0d","type":"inject","z":"2ff624305b8cb30b","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":230,"y":300,"wires":[["1f3f938edf2e8c81"]]},{"id":"6e804d72c4c1c473","type":"debug","z":"2ff624305b8cb30b","name":"调试 2","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":570,"y":300,"wires":[]}]

2. 全局变量

函数计算读取DO_1即第一路继电器的状态，如果此时流程内没有继电器输出节点，则会提示未定义：

边缘计算网关/物联网平台/网关模块/纵横智控