IoT Protocol -- Modbus

2021-02-20. Category & Tags: IoT, Modbus, RS232, RS485, RS422, Serial, COM, CAN1939, MQTT, Emulator, Simulator

OSI vs. Modbus Layers: Tip: RS-485/RS485’s new name is EIA-485. UART usually (99%) means TTL in shops, not 232/485. DB9 physical port usually (90%) means 232 electrical signals level standards. Modbus Protocol # See Also: 【strongly recommend!】 a nice intro to Modbus and Modbus Enron. (Simply Modbus 软件收费,但是这个 Modbus 入门文档非常好) 一文看懂 Modbus 协议 Complete Modbus Guide. a good intro to Modbus. Each Modbus Slave has 4 tables with 9999 values in each table. ...


2021-02-20. Category & Tags: MQTT, IoT

Server # ActiveMq Classic # Require: JAVA_HOME (JDK is preferred than JRE, if in development, as JRE ∈ JDK. 150MB) && reboot. e.g.: Apache ActiveMq (ref, bak). cd bin ./activemq-admin.bat create mybroker cd mybroker/bin/ mybroker.bat start EMQX # Require: Erlang (150MB) (will install MS VC++ Redist. 2015). ref download # hands-on # web: localhost:18083 default account: admin/public ref: EMQX dashboard, bak ref: EMQX+Prometheus+Grafana:MQTT 数据可视化监控实践, bak Client # e. ...