VIPA CP 1413plus, Руководство пользователя

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H1 Layer 4 program interface CP1413plus manual
4-36 Rev. 00/07
4.2.3.8 Start read
#include <H1Def.h>
unsigned short WENTRY_C H1StartRead(H1_RECPARAMS W_POINTER rec)
This function starts a read task.
Parameter
rec
Pointer to a structure containing receive parameters. Parameters
Vnr
and
DataLen
must contain the respective values. Ensure that the
buffer at the end of the structure is large enough.
Possible values returned by
rec.Fehler
:
0
H1_WAIT_CONNECT
H1_BLOCKED_DATA
H1_BAD_LINE
H1_WAIT_DATA
H1_NO_DRIVER
H1_NO_ADAPTER
H1_ALREADY_RUNNING
Return value
< >
0
The operating system has detected an error.
0
The
rec.Fehler
element contains one of the values mentioned
above.
Note
This function is normally executed in singletasking systems. It starts a read operation.
You may determine the result of the function by means of
H1CheckRead.
You
may not mix the
H1ReadData
and
H1StartRead
/
H1CheckRead
tasks for a
single connection.
The driver must first be initiated by means of
H1DriverOpen
and a connection
must also be established by executing
H1StartConnect
or
H1StartConnectCard
.
When a value of
H1_WAIT_SEND
is returned the
H1StartRead
function must be
repeated.
See also
H1DriverOpen
H1DriverClose
H1StartConnect
H1StartConnectCard
H1ReadData
H1CheckRead