Siemens SIMATIC FM 353, Manual

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Programming the Technological Functions
6-60
FM 353 Stepper Drive Positioning Module
6ES7 353-1AH01-8BG0
Example 2
Open the example project. The block used for this example is FC 102.
The signals are in “DBEX”. The signals relevant for Example 2 only are in structure
“EX2”.
The Drive Enable and the Controller Enable for the axis are set in “DBEX” (OB
100: DRV_EN = TRUE, SERVO_EN = TRUE), and are transferred to the interface
(AW-DB) in Example 2.
In order for the example to function, you must set the “MDI” mode. Enter “MDI”
mode (mode code 06) in the MODE_IN byte of “DBEX”. The relevant mode check-
back signal is flagged in byte MODE_OUT.
Once the mode has been successfully set, a default MDI block is automatically
transferred to the module (MDI network) when Write request “MDI_EN” has been
set in “AW-DB” (transfer MDI block). This block can be changed in dependence on
the system and the request. If it is to be retransferred, you either have to reset the
“MDI_D” bit in “AW-DB” (status/checkback signal for request) or set bit “JOBRE-
SET” (reset status/error).
Set the “START” bit in “DBEX” to TRUE in the “EX2” structure. The activated MDI
block is started on the condition that the axis is synchronized and has a Start En-
able. Then the “START” bit is reset. The MDI block cannot be restarted until the
start enable is again available.
The block can be stopped by setting the “STOP” bit.
Only when the “STOP” bit has been reset to FALSE (and the “START” bit to
TRUE) is a restart possible.
If an operator error or traversing error occurs, it is flagged by the “OT_ERR” bit
(the bit is set to TRUE). The error can be acknowledged by setting the
“OT_ERR_A” bit to TRUE.
Note:
Variable table 2, which contains all the relevant signals for monitoring and control-
ling Example 2 (“control and monitor variable” tool), is located in the “Blocks” direc-
tory.