GE VersaPoint IC220PBI002 User Manual page 128

8
<Length of PCP data>
Specifies how many bytes of PCP object data (object contents) follow.
<PCP object data>
The actual contents of a PCP object.
<PCP acknowledgment>
The structure of a PCP acknowledgment is:
<Message code> <Result> <Length of PCP data> <PCP object data> or
<Message code> <Result> <PCP error code>
<Invoke ID>
The Invoke ID is one byte in length and is used for channel selection on some
modules.
The message code is 81
function of a status byte (0 means "OK", 44
PCP data" and "PCP object data" only contain specific values on a read response
(Read). "Length of PCP data" specifies how many bytes of PCP object data
(object contents) follow. The "PCP object data" contains the actual contents of a
PCP object. In the event of an error, the status byte is directly followed by the PCP
error code.
When accessing PCP, the first byte in the DP/V1 data block uses PCP Read (= 01
) and PCP Write (= 02
hex
or written.
8-8 VersaPoint™ I/O System Profibus-DP NIU User's Manual – August 2005
(PCP Read) or 82
hex hex
means "general error"). "Length of
hex
) to indicate whether the PCP object should be read
hex
(PCP Write). The result has the
GFK-1911B