These registers, collectively referred to as the Input MTU block, are used to transfer data from the module to the superordinate system.
Control Byte in Receiving Direction
The module uses control bytes to transmit information to the superordinate system to enable it to reassemble the received frame from the individual Input MTU blocks and segments.
|
Bit |
Description |
|---|---|
|
0...5 |
0...63 = Segment length |
|
6 |
0 = Control byte for the next segment is in a new MTU (RxByte1) 1 = Control byte for the next segment follows immediately after the segment end |
|
7 |
0 = Frame is not complete 1 = Frame is complete |
Specifies the length of the frame received. Only six bits are available in the control byte, therefore 63 is the maximum segment length. If the received frame is longer than the maximum segment length, it is split into several segments with corresponding control bytes. The frame end is detected by testing bit 7 in the last segment.
Indicates the position at which to expect the next control byte.
See also Multiple Segments/Segment Size.
This bit is set in the last segment as the frame end identifier. The application can now further process the frame.
