Multitek MultiLed M812-LD Series Operating Manual page 53

5.3.6 Timing
RTU frame timing :
The message start with an interval of at least 3.5 character times.
Following the last transmitted character, a similar interval of a least
3.5 character times marks the end message.
The entire message frame must be transmitted as a continuous
stream.
5.3.7 Response time.
Modbus response time from reception of the last character to the
transmission of the 1st character in its reply is less than 200 msec.
5.3.8 Codes Supported
Function 3 (03 hex) Read holding registers. (4X)
Function 4 (04 hex) Read input registers. (3X)
Function 16 (10 hex) Preset Multiple register. (4X)
Function 17 (11 hex) Report slave ID
BROADCAST is not supported and this command does not cause the
slave to respond to the master.
An EXCEPTION error will be generated if the node cannot fulfil the
task set by the Master or the Slave receives invalid data in its data slot.
Exception code table
Code Name
01 Illegal Function
02 Illegal Data Address
03 Illegal Data Value
5.3.9 Modbus Codes Reference
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