viClear
Syntax
viClear(ViSession vi);
Description
Clear a device. This operation performs an IEEE 488.1-style clear of the device.
- For VXI, the Word Serial Clear command should be used.
- For GPIB systems, the Selected Device Clear command should be used.
- For a session to a TCPIP socket, if VI_ATTR_IO_PROT is VI_PROT_4882_STRS, the device is sent the string "*CLS\n". Otherwise, this operation is not valid.
- For a session to a serial device, this function flushes the instrument buffer. This is equivalent to calling viFlush with the VI_READ_BUF flag.
- For a session to a USB instrument, this function sends the INITIATE_CLEAR and CHECK_CLEAR_STATUS commands on the control pipe.
Parameters
Name |
Dir |
Type |
Description |
---|---|---|---|
vi |
IN |
ViSession |
Unique logical identifier to a session. |
Return Values
Type ViStatus |
This is the function return status. It returns either a completion code or an error code as follows.
|
Completion Code |
Description |
---|---|
VI_SUCCESS |
Operation completed successfully. |
Error Code |
Description |
VI_ERROR_BERR |
Bus error occurred during transfer. |
VI_ERROR_CONN_LOST |
The I/O connection for the given session has been lost. |
VI_ERROR_INV_SESSION |
The given session or object reference is invalid (both are the same value). |
VI_ERROR_INV_SETUP |
Unable to start operation because setup is invalid (due to attributes being set to an inconsistent state). |
VI_ERROR_NCIC |
The interface associated with the given vi is not currently the controller in charge. |
VI_ERROR_NLISTENERS |
No Listeners condition is detected (both NRFD and NDAC are deasserted). |
VI_ERROR_NSUP_OPER |
The given vi does not support this function. |
VI_ERROR_RAW_RD_PROT_VIOL |
Violation of raw read protocol occurred during transfer. |
VI_ERROR_RSRC_LOCKED |
Specified operation could not be performed because the resource identified by vi has been locked for this kind of access. |
VI_ERROR_TMO |
Timeout expired before function completed. |