Check for the presence of a device on the bus.
unsigned int ibln (int ud, int pad, int sad, short *listen) |
ibln pad sad
ud | Board descriptor |
pad | The primary GPIB address of the device |
sad | The secondary GPIB address of the device |
listen | Indicates if a device is present or not |
Function Return | The value of Ibsta |
ibln determines whether there is a listening device at the GPIB address designated by the pad and sad parameters. The bus associated with the board is tested for Listeners. If a Listener is detected, a non-zero value is returned in listen. If no Listener is found, zero is returned.
The pad parameter can be any valid primary address (a value between 0 and 30). The sad parameter can be any valid secondary address (a value between 96 to 126), or one of the constants NO_SAD or ALL_SAD. The constant NO_SAD designates that no secondary address is to be tested (only a primary address is tested). The constant ALL_SAD designates that all secondary addresses are to be tested.
EARG | Either the pad or sad argument is invalid. |
EBUS | No devices are connected to the GPIB. |
ECIC | The access board is not CIC. |
EDVR | The NI-488.2 driver is either configured incorrectly or is not properly installed. |
EHDL | ud is invalid or out of range. |
ELCK | The requested operation could not be performed because of an existing lock by another process. |
ENEB | The interface is not installed or is not properly configured. |
EOIP | Asynchronous I/O is in progress. |