lib freemodbus porting for esp32
you must know thise lib should be used for modbus master role.
implemented:(see components/esp-modbus/functions/)
FreeModbus是一款开源的Modbus协议栈,但是只有从机开源,主机源码是需要收费的。同时网上也没有发现比较好的开源的Modbus主机协议栈,所以才开发这款支持主机模式的FreeModbus协议栈。本版FreeModbus版本号更改为V1.6,支持Modbus主机协议栈,特性如下:
eMBMasterReqReadCoils
eMBMasterReqReadDiscreteInputs
eMBMasterReqReadHoldingRegister
eMBMasterReqReadInputRegister
eMBMasterReqWriteCoil
eMBMasterReqWriteHoldingRegister
eMBMasterReqWriteMultipleCoils
eMBMasterReqWriteMultipleHoldingRegister
eMBMasterReqReadWriteMultipleHoldingRegister
--now add rs485 support (note:this demo rs485 en pin using gpio12)--
thanks armink ! more reference seeing his git>https://github.com/armink/FreeModbus_Slave-Master-RTT-STM32