Siemens SIMATIC MV420, Operating Instructions Manual

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Process interfacing via an automation system (PLC, PC)
10.3 Control with FB 45 and Ident profile
SIMATIC MV420 / SIMATIC MV440
Operating Instructions, 04/2013, A5E02371045-06
253
Command: Read match string
● The "Read match string" MV command is used to prepare reading of the match string.
The actual read is not executed with the WRITE command.
● The command data area of the WRITE command contains only the command identifier.
● Send the "Read match string" command with the WRITE command and wait for the
positive response. Then read out the actual string with a READ command.
● The WRITE command must specify a length of 0x1 ("MOBY_CMD".length or
"PIB_COMMAND".Length = 0x1), otherwise a negative response will be sent.
Table 10- 16 Moby_CMD
Command
[hex]
Sub_
Command
[hex]
Length
[dez]
Address_
MDS [hex]
DAT_DB_number
[dez]
DAT_DB_address
[dez]
Number of the
data DB (for example
48)
Pointer to the start
word
(for example 0)
01 - 1 0
Pointer to the user data to be sent to the
reader.
Table 10- 17 PIB_COMMAND
Parameter Value
CMD 0x71
OffsetBuffer 0x00
UID 0x00
Length 0x01
StartAddress 0x00
Table 10- 18 Command data area (FB45: Data DB, RFID standard profile: TXBUF or RXBUF)
Address Value Meaning
0x0000 0x04 Command identifier
"Read match string"