Siemens SIMATIC S7-1500 Manual page 25

Position of the PQI byte in the process image (example):
Figure 4-2 Address space IO-Link Master
In the example above, 16 bytes are set for port 1, the IO-Link device transfers the data in
bytes 0 to 7 and the PQI byte is set to byte 15.
NOTE
Restriction
The graphic only applies to the input range.
Standard DI mode
The following figure shows the assignment of the address space of a port for the IO-Link
Master CM 8xIO-Link, if you have configured the port as a digital input.
Figure 4-3 Address space of the inputs of the IO-Link Master CM 8xIO-Link in standard DI mode
Reference
You can find additional information in the IO-Link System
(https://support.automation.siemens.com/WW/view/en/65949252) function manual.
Communication module IO-Link Master CM 8xIO-Link (6ES7547-1JF00-0AB0)
Equipment Manual, 08/2022, A5E45488510-AB
Parameters / address space
4.3 Address space
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