Lock the ACIA settings in the M550/M560/M570 transducer.
A few seconds after being connected to a live Modbus network, the transducer will configure itself to the networks settings. i.e. baud rate, parity, stop bits.
N.B. A true Modbus character format is always 11 bits, therefore, if NO parity is selected there must be 2 stop bits.
(however, due to user demand the M550s, M560s and M570s are able to communicate using a format of 1 start, 8 data, no parity and 1 stop bit)
If the transducer detects 5 consecutive framing errors, it will start to search using different parity settings until the errors stop.
If the transducer detects 5 consecutive CRC errors, it will start to search using different baud rate settings until the errors stop.
To prevent unnecessary hunting the settings can be locked into the EEPROM and will always be used unless they are unlocked again.
In addition to the General Pass Code being valid, another code, found below, needs to be sent as data with this function.
For M550 and M560 transducers, the write functions require the General Pass Code to be valid.
Slave Address = 1
Writing To 4X Registers - code 16 (10 hex)
Message Packet To SLAVE
01 10 00 60 00 02 04 46 A3 50 00 2C ED
N.B. 46 A3 50 00 = 20904
Response Packet From SLAVE
01 10 00 60 00 02 41 D6