Festo VTEM - Page 61

Festo — VTEM — 2021-05f
Function
61
3.5.4.3 Feedback in the case of invalid output data
If invalid information is transmitted as part of the output data, corresponding feedback is provided in
the input data in transfer mode:
– Operating mode of the valve (valve mode): 63 (transfer mode active) (PDI byte 0, bits 5 … 0 =>
111111
2
)
– Status of the valve: valve state
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3.5.2.2 Structure of the input data (PDI).
– Channel (channel): not assigned (PDI byte 1, bits 4 … 0 => 0)
– Transfer control (transfer control): not assigned (PDI byte 1, bits 7… 5 => 0)
–
Addressing of data transfer (addressed target): not assigned (PDI byte 2 => 0)
–
Index (index): not assigned (PDI byte 3 => 0)
– Value (value): (PDI byte 5 … 4)
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Tab. 73 Allocation of invalid information
Allocation of invalid information
The “value” (value) section indicates which part of the output data contains invalid information.
Value Invalid command Meaning
1 invalid channel Invalid value in section "channel"
2 invalid transfer control Invalid value in section "transfer control"
3 invalid addressed target Invalid value in section "addressed target"
4 invalid index Invalid value in section "index"
5 invalid value Invalid value in section "value"
6 invalid combination Invalid combination of values in various sections
7 access denied, data in use The addressed data is currently being used by
another valve
8 no data, slot is empty The addressed data are not available because
a valve is not mounted on the slot via which
process data is communicated.
Tab. 73: Allocation of invalid information
Example of input data with incorrect value in section "index"
PDI byte 1 PDI byte 0
Command
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
0 0 0 0 0 0 0 0 ... ... 1 1 1 1 1 1
transfer control
= 0
channel = 0 valve state valve mode = 63 (transfer mode)
PDI byte 3 PDI byte 2
Parameter