Translations:Modbus RTU в виде custom protocol/9/en

function readRegister (reg, device, unitId)

                            --- FORMING REQUEST ----------- 
     -- slave address
 request[1] = unitId;
 
 -- function code
 request[2] = device.xtraFields[1]
 
 -- address of register
 request[3] = GetHiByte(reg.internalAddr)
 request[4] = GetLoByte(reg.internalAddr)
 
 -- count of registers
 local count = 1
     if (reg.dataType == 3) then -- double word
       count = 2
     end
 request[5] = GetHiByte(count)
 request[6] = GetLoByte(count)
 
  -- CRC
 local crc = GetCRC(request, 2)
 local crcLo,crcHi = 0,0 -- will be used below too 
 crcLo = GetLoByte(crc) ; request[7] = crcLo
 crcHi = GetHiByte(crc) ; request[8] = crcHi