Bender B95061094, Руководство по установке

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Modbus TCP server
24 CP9xx-Kit_D00399_00_M_XXEN/07.2019
5.1.4 Structure of the exception code
5.1.5 Modbus address structure for BMS devices
5.2 Modbus process image in the memory of the CP9…
The device holds a process image in memory. This image represents the current states and values of all devices
that are in the same system as the CP9…
5.2.1 Querying data
5.2.1.1 Modbus function code FC03
The parameters and measured values of all devices in the subsystem can be read using the Modbus function
0x03 "Read Holding Registers". This is only possible on the subsystem level, not in the entire system. The unit
ID refers to the respective device address.
5.2.1.2 Modbus function code FC04
The process image in the memory of the CP9… can be read using the Modbus function 4 "Read Input Regis-
ters". Device name, device channel states and alarm and operating messages can be accessed via this function.
This is possible for all devices in the system. Here, the unit ID refers to the subsystem address.
The volume of the queried data depends on the number of bytes selected in the Modbus client used. Up to 125
words (0x7D) can be read with a single query.
An individual word can also be read, for example, to detect the set bit for a saved common alarm.
5.2.1.3 How are the memory areas organised?
The assignment of the memory addresses and the associated memory content for one subsystem is described
below. Please refer also to the "BCOM" manual, which provides information about the entire addressable sys-
tem.
Byte Name Example
… … …
Byte 7 MODBUS function code 0x84
Byte 8 Exception code 0x01 or 0x02
Function Address range Number of bytes
Number of
words
Device type 0x00…0x09 20 bytes 10 words
Timestamp 0x0A…0x0D 8 bytes 4 words
Common alarm 0x0E (high byte) 1 byte 0.5 words
No BMS bus con-
nection
0x0E (low byte) 1 byte 0.5 words
Unused 0x0F 2 bytes 1 word
Channel 1…32 0x10…0x8F 32 x 8 bytes 128 words
Alarm and test
Channel 33…64
0x90…0xFC 218 x 8 bytes 109 words
Memory utilisation Start address End of memory area
Size of memory area
Reference values
for test purposes
0x0000 0x00FF 0x0100
Process image 0x0100 0x95FF 0x9500
Unused 0x96FF 0xFFFF 0x6900
For some Modbus clients an offset of 1 must be added to the register addresses.
Example: process image start address = 0x0101.