Reads bytes from a specified VXI Message Based device.
[ lStatus = ] VxiReceive ( lLA, sEOS, bEND, lTimeout [, enMode] , pDst [, lBytes ] )
The VxiReceive procedure syntax has the following parts:
|
Name |
Type |
Description |
|
lStatus |
Long |
Bytes actually received |
|
lLA |
Val Long |
Device logical address |
|
sEOS |
Val BString |
End of sequence string |
|
bEND |
Bool |
A Boolean expression specifying whether or not to terminate the transmission upon the End bit. |
|
lTimeout |
Val Long |
Timeout in milliseconds |
|
enMode |
Val enumAIoMode |
Input read mode. The deafult is 0, aioDefault. |
|
pDst |
Var Any |
Receive data buffer |
|
lBytes |
Val Long |
Maximum number of bytes to receive. If the default value is used (-1) the byte length of the pDst is used as the maximum of bytes to receive. |
bEND can have one of the following values:
|
Value |
Description |
|
True * |
Terminate the transmission upon the END bit. |
|
False |
The END bit is ignored (similar to GPIB EOI). |
enumAIoMode can have one of the following values:
|
Name |
Value |
Description |
|
aioImmediate |
0 * |
Receive on data available |
|
aioWaitGpibSrqVxiDor |
1 |
Receive on Srq (gpib) or on Dor (vxi) |
|
aioGpibImmediateOrSrq |
2 |
Receive on Immediate or Srq (gpib) |
|
aioDisableBstrConvert |
4 |
Disable conversion of BString to String, can be combined with 1 of the previous values. |
The lLA contains the logical address of the device and may be obtained using the GetDriverAddress function.
The sEOS can be 0-2 bytes long and specifies the data bytes that signal the end of data (terminator).
If lBytes is not given (-1), then it is set to the length of the data buffer.
This function returns the number of bytes received. A value of -1 indicates failure.
The following command reads data device to the string sData at Logical Address 19. The timeout is set to 1500 mSec, the terminator used is Line Feed:
VxiReceive(19, "\n", True, 1500, ,sData)