Programming without SFB 52 and SFB 53
D.11 Fast access to module data
FM 352 electronic cam controller
Operating Instructions, 05/2011, A5E01071724-03
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D.11 Fast access to module data
Application
Very fast access to checkback and control signals is required in special applications or in an
alarm level. You can access these data directly via the input and output areas of the module.
To coordinate startup following each module startup (for example, after inserting a module,
CPU STOP → RUN), call FC CAM_CTRL continuously until the end of the startup is
indicated by RET_VAL = 0.
Note
For direct access to FM 352 data, always use the non-internal data and method described in
this section. Otherwise, your user program will encounter difficulties accessing the module.
Reading checkback signals via direct access
The byte addresses are specified relative to the output address of the module. The bit
names correspond to the names in the channel DB.
In STL, you access the data using the PIB (read 1 byte) and PID (read 4 bytes) commands.
Address Bit number
7 6 5 4 3 2 1 0
Byte 0 PARA Interna
l
Internal DATA_ERR Internal DIAG Internal Internal
Byte 1 0 0 0 CAM_ACT 0 0 0 0
Byte 2 Internal
Byte 3 0 0 FVAL_DONE HYS GO_P GO_M MSR_DONE SYNC
Byte 4
Byte 5
Byte 6
Byte 7
ACT_POS
Byte 8
Byte 9
Byte 10
Byte 11
TRACK_OUT