84 - IO Data Handling
DeviceMaster PNIO | UP User Guide
: 2000639 Rev. A
IO Data Handling
Packets from different serial ports and Ethernet devices are combined and sent to
IO controller in one PROFINET IO frame.
For example, a PNIO-2304 or DeviceMaster UP 4-port panel mount has 6 220-byte
input submodules configured for 4 serial ports and 2 Ethernet devices. There are
multiple packets waiting in the receiving queue on all 6 ports/devices. At the first
IO update cycle, the DeviceMaster takes one packet from each receiving queue,
combines them into one PROFINETI IO frame and sends it to the IO controller.
The total amount of input data in that PROFINET IO frame is:
(4 bytes sequence number and 220 bytes data) x 6 = 1344 bytes
At the next IO cycle update cycle, the DeviceMaster sends another PROFINET IO
frame with all new input data.