ibsad() sets the GPIB secondary address
of the device or board specified by the descriptor ud
.
If ud
is a device descriptor, then the setting is
local to the descriptor (it does not affect the behaviour of calls using
other descriptors, even if they refer to the same physical device). If
ud
is a board descriptor, then the board's
secondary address is changed immediately, which is a global change affecting
anything (even other processes) using the board.
This library follows NI's unfortunate convention of adding 0x60 hexadecimal (96
decimal) to
secondary addresses. That is, if you wish to set the secondary address
to 3, you should set sad
to 0x63. Setting
sad
to 0 disables the use of secondary addressing.
Valid GPIB secondary addresses are in the range from 0 to 30 (which correspond
to sad
values of 0x60 to 0x7e).