Configuring technology I/Os (X142) as isochronous

Requirements

STEP 7, V16 or higher

SIMATIC Drive Controller has been configured.

At least one axis technology object has been created at the CPU of the SIMATIC Drive Controller.
See for example Configuring drives with SINAMICS Integrated isochronously.

Procedure

Open the device view of the CPU.

Configure the operating modes of the technology I/Os in the CPU properties under "General" > "DI/DQ 8x24VDC[X142]" > "Channel parameters", for example, a timer DQ for later use as a cam output for channel 0.


图片: Setting the operating mode for technology I/O X142

In the project tree under the axis technology object, add an output cam technology object under "Output cam" > "Add new output cam".

Open the configuration of the output cam.

Under "Hardware interface", select the "Activate output" checkbox and the option "Output over Timer DQ".

Assign the configured output under "Output".


图片: Assigning a channel to the output cam

Use the "Device configuration" button to switch back to the CPU settings and check the settings under "DI/DQ 8x24VDC [X142]" > "I/O addresses".

The following settings must be configured for the input and output addresses:

- "Isochronous mode" is enabled.

- The organization block "MC Servo" is selected.

- The process image "OB Servo PIP" is selected.

Automatic settings

Isochronous mode is mandatory for certain operating modes of the X142 technology I/O channels.

As soon as you set one of the following operating modes for a technology I/O channel, STEP 7 automatically selects the option "isochronous mode".

Timer DI

Timer DQ

Oversampling DI

Oversampling DQ

Event/period measurement

If you assign an output cam, cam track or measuring input technology object to an X142 I/O, STEP 7 automatically sets the process image "OB Servo PIP".

In all other cases, you set the process image manually. If isochronous mode is mandatory for at least one technology I/O, you must set the process image of the "MC Servo" OB (OB91) or an isochronous mode interrupt OB (OB6x).

Setting the clock system

You have configured the technology I/Os as isochronous. Next, set the clock system.

Make the following settings in accordance with whether you are operating the X142 technology I/Os in independent or coupled isochronous mode:

For independent isochronous mode or if the X142 technology I/Os are the leading clock system

- Set the required cycle time.

- Assign the "MC Servo" OB the clock system of the technology I/Os.

For coupled isochronous mode:

- Assign the leading clock system to the clock system of the technology I/Os.
You can find details of how to assign the leading clock system in Setting the clock system.