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reaper7 / SDM_Energy_Meter

reading SDM72 SDM120 SDM220 SDM230 SDM630 modbus energy meters from arduino (esp8266, esp32, avr)
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direct reading of RS485 without converter #6

Closed ilgrank closed 7 years ago

ilgrank commented 7 years ago

Hi At low bitrates (up to 9600baud) shouldn't the ESP8266 alone be enough to read an RS485 without a converter? https://github.com/plieningerweb/esp8266-software-uart https://github.com/peninquen/Modbus-Energy-Monitor-Arduino

thanks for your work!

reaper7 commented 7 years ago

No, RS485 uses two wire differential transmission.

Project: https://github.com/plieningerweb/esp8266-software-uart for rs485 transmission, still must use a MAX485 converter: https://github.com/plieningerweb/esp8266-software-uart#how-to-use-rs485-support

Modbus-Energy-Monitor-Arduino also uses converter: https://github.com/peninquen/Modbus-Energy-Monitor-Arduino/blob/master/dev%20version/esp8266modbusEnergyMonitor/esp8266-sdm120c-Aledav.jpg

ilgrank commented 7 years ago

Thanks for the quick and kind update, I had misunderstood that Again, many thanks!