Lock ACIA
Settings
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.
Sample Coding
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