Modbus Ascii Protocol - Siemens SENTRON ATC6300 Manual

The following reply is sent by the ATC6300:
01
01 = ATC address (Slave 01)
04 = Function requested by the master
04 = Number of bytes that the ATC sends
00000007 = Hexadecimal value for the number of alarms for changeovers of Breaker 1 = 07
BA 46: CRC Checksum
11.3

MODBUS ASCII protocol

The MODBUS ASCII protocol is normally used for applications in which communication
takes place via several modems.
The available functions and addresses are the same as for the RTU version, except that the
characters are transmitted in ASCII and the end of a message is transmitted by
Carriage return / Line Feed (CR LF).
If the ASCII mode is used in Menu P08 under the parameter P8.x.05, the communication
must comply with the following structure:
Address: Contains the serial address of the slave target device.
Function: Contains the code of the function that is performed by the slave.
Data: Contains the data that is sent to the slave, or the data of a query received by the slave
(maximum length 80, 16-bit register).
LRC: This is used for an integrity check. If a message is corrupted by electric noise or
interference, the LRC field enables the ATC6300 to detect the error and thus ignore the
message.
CRLF: The message ends with CRLFcontrol characters (0D 0A).
3KC ATC6300 transfer control device
Manual, 03/2018, L1V30535632002A-01
04 04
Address
: (2 chars)
00 00 00
Function Dates
(2 chars) (N chars)
MODBUS communication
11.3 MODBUS ASCII protocol
07 BA 46
LRC CR LF
(2 chars)
149