Tio_Dq: Output Edges Time-Controlled At The Digital Output - Siemens SIMATIC ET 200AL System Manual

Programming
4.3 Time-based IO
4.3.5

TIO_DQ: Output edges time-controlled at the digital output

Description
You can use Time-based IO with the TIO_DQ instruction. TIO_DQ switches the digital output
of a TM Timer DIDQ at a specified time.
Startup characteristics
During startup of the CPU, the instruction TIO_DQ applies the input parameters once and
checks the following:
● Checking HWID
● Checking to see if the number of the digital input (Channel) is in the permitted range
(depending on addressed module and channel configuration)
● Checking TIO_SYNC_Data.Error: Is an error present at TIO_SYNC?
● Checking T
● Checking whether the OB is a "Synchronous Cycle" OB
If startup takes place without errors, the instruction changes to normal operation. The input
parameters REQ , Out_Mode, TimeStampRE and TimeStampFE can be changed during
normal operation. In the event of an error, the instruction does not change to normal
operation and generates an error message.
Operating principle
The instruction outputs edges time-controlled at a digital output during normal operation.
● At the time defined at the TimeStampRE input parameter, a positive edge is output at the
digital output.
● At the time defined at the TimeStampFE input parameter, a negative edge is output at the
digital output.
Use the input parameter Out_Mode to determine if only one edge or both edges are output.
You connect the input TIO_SYNC_Data with the output of the same name of the TIO_SYNC
instruction. This ensures a shared time basis.
You start an output job with a positive edge at the "REQ" parameter. You can only start a
new job when there is no error pending and no job is active. When the output job is started,
the digital output is switched at the times defined with TimeStampRE and TimeStampFE.
● If the digital output is already set at time TimeStampRE, the output job is not transferred
to the module for the positive edge.
● If the digital output is not set at time TimeStampFE, the output job is not transferred to the
module for the negative edge.
This means the digital output is not switched in both cases.
The job is done when the last application cycle is executed before the second output time is
reached (DONE). Status and Error are constantly being updated during the job runtime.
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for validity (0 ms to 4 ms)
o
High-precision input/output with Time-based IO
Function Manual, 08/2014, A5E33454822-AB