Racal Instruments 3155, User Manual

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User Manual 3155
Programming Reference 4-9
The 3155drv.dll
Functions The 3155drv DLL controls the complete functionality of the instru-
ment. You also have to use this DLL to communicate with your in-
strument. Communication with the instrument is done using SCPI
commands. The SCPI commands by themselves cannot program the
instrument but must be used with conjunction with the 3155drv DLL.
There are two library functions that call this DLL. These functions are
described below.
SendCommand
Purpose
Use this function to send SCPI commands to the instrument
C Syntax
INSTRUMENTSTATE SendCommand (int hInstr, char *inbuf)
Resource Classes
PXI, PCI
Parameters
Name
Description
hInstr
Instrument handle number. Must be within the a range of instruments that were found in the PXI bas-
kets. The numbers start at 0 (for first device) to n-1. This value is extracted using the RIComm.dll
function FindInstrument()
inbuf
Contains one or more SCPI commands. 256 characters limit the number of characters in this buffer.
The commands must be terminated by ‘\0’. If the inbuf contains queries, the returned strings are
placed in the inbuf and, also in this case, the size is limited to 256 characters.
Return Values
Completion Codes
Description
PCI_SUCCESS
Function executed without errors
PCI_INS_ALREADY_OPEN
Trying to establish new communication link while instrument has already been connected.
Error Codes
Description
PXI_COMMAND_ERROR
if the value is 0x8000000, error is in SCPI syntax or other errors relating to instrument setability
.SCPI error list is given in the SCPI Commands reference.
If the value is larger than 0x8000000, look for problems in the communication with the 3155. The
most probable cause for such errors is not invoking the Arb Detector program after you power up
your computer.