Matrox Solios eV-CL - Page 61

Matrox Solios eV-CL acquisition section 61
User signals
Auxiliary signals can also be used to transmit or receive application-specific user
output and/or input.
If you want to start or stop an external event based on some calculation or analysis,
you can manually set the state of any auxiliary output signal (or I/O signal set to
output) to high or low. To do so, you set the state (on/off) of a bit in a user settable
register (static-user-output register). When the bit is on, its associated auxiliary
output signal will be high; when it is off, the auxiliary output signal will be low.
This bit is referred to as a user-bit.
Your application can also act upon and interpret the state of an auxiliary input
signal (or I/O signal set to input). The state of an auxiliary input signal is not
associated with a user-bit; you poll the state of the signal directly. The state of an
auxiliary input signal can also generate an interrupt.
To route the state of a user-bit to an auxiliary output signal, use MdigControl()
with M_IO_SOURCE
*
and M_USER_BITn; to set the state of a user-bit, use
MdigControl() with M_USER_BIT_STATE. To poll the state of an auxiliary
input signal, use MdigInquire() with M_IO_STATUS
*
; whereas to have the
signal cause an interrupt, use MdigControl() with
M_IO_INTERRUPT_STATE and then use MdigHookFunction() with
M_IO_CHANGE to hook a function to this event (that is, to set up an event
handler).
*. As of MIL 10.