viGpibControlATN
Syntax
viGpibControlATN(ViSession vi, ViUInt16 mode);
Description
Controls the state of the GPIB ATN interface line, and optionally the active controller state of the local interface board. This operation asserts or deasserts the GPIB ATN interface line according to the specified mode. The mode can also specify whether the local interface board should acquire or release Controller Active status.
This operation is valid only on GPIB INTFC (interface) sessions.
Note: It is generally not necessary to use the viGpibControlATN operation in most applications. Other operations such as viGpibCommand and viGpibPassControl modify the ATN and/or CIC state automatically.
Parameters
|
Name |
Dir |
Type |
Description |
|
vi |
IN |
ViSession |
Unique logical identifier to a session. |
|
mode |
IN |
ViUInt16 |
Specifies the state of the ATN line and, optionally, the local active controller state. |
|
Special Values for mode Parameter |
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Value |
|
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Action Description |
|
VI_GPIB_ATN_ASSERT |
|
|
Assert ATN line synchronously (in 488 terminology). If a data handshake is in progress, ATN will not be asserted until the handshake is complete. |
|
VI_GPIB_ATN_DEASSERT |
|
|
Deassert ATN line. |
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VI_GPIB_ATN_DEASSERT_HANDSHAKE* |
|
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Deassert ATN line, and enter shadow handshake mode. The local board will participate in data handshakes as an Acceptor without actually reading the data. |
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VI_GPIB_REN_ASSERT_IMMEDIATE* |
|
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Assert ATN line asynchronously (in 488 terminology). This should generally be used only under error conditions. |
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* 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 Code |
Description |
|
VI_SUCCESS |
Operation completed successfully. |
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Error Codes |
Description |
|
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). |
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VI_ERROR_NCIC |
The interface associated with this session is not currently the controller in charge. |
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VI_ERROR_NSUP_MODE |
The specified mode is not supported by this VISA implementation. |
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VI_ERROR_NSUP_OPER |
The given vi does not support this operation. |
|
VI_ERROR_RSRC_LOCKED |
Specified operation could not be performed because the resource identified by vi has been locked for this kind of access. |
See Also
INTFC resource description