Read_Mv - Siemens Simatic Ident Function Manual

Parameter
EPCID_UID
IDENT_DATA
You can find additional information on working with optical reader systems in the operating instruc-
1)
tions for "SIMATIC MV420 / SIMATIC MV440" and "SIMATIC MV500".
3.4.1.2

Read_MV

The "Read_MV" block reads out the read result of an optical reader. The "Read" block must
be used to read the configuration. The length of the data to be read is calculated
automatically by the block based on the length of the created receive buffer. The actual
length of the read result is output in the "LEN_DATA" output parameter. The data will be
saved in the "IDENT_DATA" data buffer. If the buffer is too small, the error message
"0xE7FE0400" appears and the expected length is output at "LEN_DATA".
To achieve an optimum speed, we recommend that you adapt the length of the data type
"IDENT_DATA" so that this is as close as possible to the maximum expected length of the
read result (2 bytes code length + read code).
Figure 3-6
Ident profile and Ident blocks, standard function for Ident systems
Function Manual, 10/2018, C79000-G8976-C387-04
Data type
Array[1...62] of
Byte
Any / Variant
"Read_MV" block
Default values Description
0 Buffer for up to 62 bytes EPC-ID, 8
bytes UID or 4 bytes handle ID.
2 - 62-byte EPC-ID is entered at
•
the start of the buffer (length is set
by "LEN_ID")
8-byte UID is entered at the start
•
of the buffer ("LEN_ID = 8")
4-byte handle ID must be entered
•
in the array element [5]-[8]
("LEN_ID = 8")
Default value: 0x00 ≙ unspecified
single tag access (RF620R, RF630R)
0 Data buffer in which the read data is
stored.
Note:
For Variant, currently only an "Ar-
ray_of_Byte" with a variable length
can be created. For Any, other data
types/UDTs can also be created.
Setting parameters for blocks
3.4 Programming Ident blocks
25