Siemens Siwarex U, Device Manual

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7BCOMMUNICATION IN SIMATIC S7
8.3 SIWAREX U in the cyclical STEP 7 program
SIWAREX U communicates with the SIMATIC CPU using the function block FB
SIWA_ U. When programming the call, an instance data block is created for the FB
SIWA_U. Alongside the instance data block, a scale DB is required
for each
SIWAREX U
, in which the scale parameters can be stored. To create the
Scale_DB, the UDT delivered along with it can be used.
In addition, the vector DB must be loaded in the SIMATIC CPU.
A vector DB can
be used by several SIWAREX U
.
The function block FB SIWA_U and the data blocks are to be found on the CD of the
configuration package SIWAREX U for SIMATIC S7 in the project "Getting started".
The function block prepares specific current process values cyclically without data
set communication (via the peripheral area) and supports on request (commands)
the data record communication with the aid of internal calls of the SFB 52/53
modules.
CALL "SIWA_U", DB 10 (
ADDR := 256,
DB_SCALE := 9,
DB_VECTOR := 8,
CMD_IN := "DB_SIWA_U".i_CMD_CODE_INPUT,
CMD_INPR := "DB_SIWA_U".bo_CMD_IN_PROGRESS,
CMD_FOK := "DB_SIWA_U".bo_CMD_FINISHED_OK,
CMD_ERR := "DB_SIWA_U".bo_CMD_ERR,
CMD_ERR_C := "DB_SIWA_U".b_CMD_ERR_CODE,
REF_COUNT1 := "DB_SIWA_U".b_CYCLE_COUNT_CH1,
SC_STATUS1 := "DB_SIWA_U".b_SCALE_STATUS_CH1,
ASYNC_ERR1 := "DB_SIWA_U".w_OPR_ERR_MSG_CH1,
GROSS1 := "DB_SIWA_U".i_GROSS_WEIGT_CH1,
FLT_RAW1 := "DB_SIWA_U".w_ADC_VALUE_FILTERED_CH1,
REF_COUNT2 := "DB_SIWA_U".b_CYCLE_COUNT_CH2,
SC_STATUS2 := "DB_SIWA_U".b_SCALE_STATUS_CH2,
ASYNC_ERR2 := "DB_SIWA_U".w_OPR_ERR_MSG_CH2,
GROSS2 := "DB_SIWA_U".i_GROSS_WEIGT_CH2,
FLT_RAW2 := "DB_SIWA_U".w_ADC_VALUE_FILTERED_CH2,
FB_ERR := "DB_SIWA_U".bo_FB_ERR,
FB_ERR_C := "DB_SIWA_U".b_FB_ERR_CODE,
START_UP := "DB_SIWA_U".bo_STARTING_UP,
RESTART := "DB_SIWA_U".bo_RESTART,
CMD_EN := "DB_SIWA_U".bo_CMD_TRIGGER);
Figure 8-1 Call parameters of the FB SIWA_U
8-52
SIWAREX U