viVxiCommandQuery
Syntax
viVxiCommandQuery(ViSession vi, ViUInt16 mode, ViUInt32 cmd, ViPUInt32 response);
Description
Send the device a miscellaneous command or query and/or retrieve the response to a previous query. This operation can send a command or query or receive a response to a query previously sent to the device. The mode parameter specifies whether to issue a command and/or retrieve a response, and what type or size of command and/or response to use.
If the mode parameter specifies sending a 16-bit command, the upper half of the cmd parameter is ignored. If the mode parameter specifies just retrieving a response, the cmd parameter is ignored. If the mode parameter specifies sending a command only, the response parameter is ignored and may be VI_NULL. If a response is retrieved but is only a 16-bit value, the upper half of the response parameter will be set to 0.
Refer to the VXI Specification for defined word serial commands. The command values Byte Available, Byte Request, Clear, and Trigger are not valid for this operation.
Parameters
|
Name |
Dir |
Type |
Description |
|
vi |
IN |
ViSession |
Unique logical identifier to a session. |
|
mode |
IN |
ViUInt16 |
Specifies whether to issue a command and/or retrieve a response. See the Description section for actual values. |
|
cmd |
IN |
ViUInt32 |
The miscellaneous command to send. |
|
response |
OUT |
ViPUInt32 |
The response retrieved from the device. If the mode specifies sending a command, this parameter may be VI_NULL. |
|
Special Values for mode Parameter |
|||
|
mode |
|
|
Action Description |
|
VI_VXI_CMD16 |
|
|
Send 16-bit Word Serial command. |
|
VI_VXI_CMD16_RESP16 |
|
|
Send 16-bit Word Serial query, get 16-bit response. |
|
VI_VXI_CMD32* |
|
|
Send 32-bit Word Serial command. |
|
VI_VXI_CMD32_RESP16* |
|
|
Send 32-bit Word Serial query, get 16-bit response. |
|
VI_VXI_CMD32_RESP32* |
|
|
Send 32-bit Word Serial query, get 32-bit response. |
|
VI_VXI_RESP16* |
|
|
Get 16-bit response from previous query. |
|
VI_VXI_RESP32* |
|
|
Get 32-bit response from previous query. |
|
* Not supported in Agilent VISA |
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Return Values
|
Type ViStatus |
This is the function return status. It returns either a completion code or an error code as follows. |
|
Completion Codes |
Description |
|
VI_SUCCESS |
Operation completed successfully. |
|
Error Codes |
Description |
|
VI_ERROR_BERR |
Bus error occurred during transfer. |
|
VI_ERROR_INP_PROT_VIOL |
Device reported an input protocol error occurred during transfer. |
|
VI_ERROR_INV_MODE |
The value specified by the mode parameter is invalid. |
|
VI_ERROR_INV_SESSION |
The given session or object reference is invalid (both are the same value). |
|
VI_ERROR_NSUP_OPER |
The given vi does not support this function. |
|
VI_ERROR_OUTP_PROT_VIOL |
Device reported an output protocol error occurred during transfer. |
|
VI_ERROR_RAW_RD_PROT_VIOL |
Violation of raw read protocol occurred during transfer. |
|
VI_ERROR_RAW_WR_PROT_VIOL |
Violation of raw write protocol occurred during transfer. |
|
VI_ERROR_RESP_PENDING |
A previous response is still pending, causing a multiple query error. |
|
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. |
See Also
INSTR Resource Description