Siemens MD-12HD, User Manual, Page: 58 / 74

57 Siemens Industry, Inc.
String example 1: Change a Static IP Address
Change the IP address of a meter from 192.168.2.8 to 192.168.2.9
It may be tempting to update only the digit “8” to “9” in the IP address, but this will NOT perform as expected.
Internally, the meter uses a single string buffer for all string register operations and unspecified entrees will
continue to contain the previous buffer contents unless specifically written to. Write every register from the
beginning of the block to the end.
Reg (dec) 1079 1080 1081 1082 1083 1084 1085 1086
Reg (hex) 04 37 04 38 04 39 04 3A 04 3B 04 3C 04 3D 04 3E
Value (Chr) ‘1’ ‘9’ ‘2’ ‘.’ ‘1’ ‘6’ ‘8’ ‘.’ ‘2’ ‘.’ ‘9’ NUL NUL NUL NUL NUL
Value (hex) 31 39 32 2E 31 36 38 2E 32 2E 39 00 00 00 00 00
START STOP
Specific Implementation Examples – Element A set to ID 1
Note that in Modbus the CRC communicated is LSB then MSB.
VIA MODBUS RTU (SERIAL) USING FUNCTION CODE 6 / WRITE SINGLE REGISTER
ID FC ADDR DATA CRC
01 06 04 37 31 39 EC B6
01 06 04 38 32 2E 9C 4B
01 06 04 39 31 36 CD 71
01 06 04 3A 38 2E 3B 2B
01 06 04 3B 32 2E 6C 4B
01 06 04 3C 39 00 5A A6
01 06 04 3D 00 00 19 36
01 06 04 3E 00 00 E9 36
VIA MODBUS RTU (SERIAL) USING FUNCTION CODE 16 / WRITE MULTIPLE REGISTER
ID FC ADDR #REGS LN DATA0 DATA1 DATA2 DATA3 DATA4 DATA5 DATA6 DATA7 CRC
01 10 04 37 00 08 10 31 39 32 2E 31 36 38 2E 32 2E 39 00 00 00 00 00 9B 99
VIA MODBUS TCP (ETHERNET) USING FUNCTION CODE 6 / WRITE SINGLE REGISTER
TXNID PROID LENGT ID FC ADDR DATA (TXNID will be arbitrary)
01 87 00 00 00 06 01 06 04 37 31 39
01 88 00 00 00 06 01 06 04 38 32 2E
01 89 00 00 00 06 01 06 04 39 31 36
01 8A 00 00 00 06 01 06 04 3A 38 2E
01 8B 00 00 00 06 01 06 04 3B 32 2E
01 8C 00 00 00 06 01 06 04 3C 39 00
01 8D 00 00 00 06 01 06 04 3D 00 00
01 8E 00 00 00 06 01 06 04 3E 00 00
VIA MODBUS TCP (ETHERNET) USING FUNCTION CODE 16 / WRITE MULTIPLE REGISTER
TXNID PROID LENGT ID FC ADDR #REGS LN DATA0 DATA1 DATA2 DATA3 DATA4 DATA5 DATA6 DATA7
01 87 00 00 00 17 01 10 04 37 00 08 10 31 39 32 2E 31 36 38 2E 32 2E 39 00 00 00 00 00