User Signals - Matrox CronosPlus Installation And Hardware Reference

26 Chapter 4: Hardware reference

User signals

Matrox CronosPlus has three TTL auxiliary input signals that can be used to
receive application-specific user input and four TTL auxiliary output signals that
can be used to transmit user output.
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 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. To set the state of a user-bit, use MsysControl() with
*
M_USER_BIT_STATE .
Your application can also act upon and interpret the state of an auxiliary input
signal. The state of an auxiliary input signal is not associated with a user-bit; you
poll the state of the signal directly. To poll the state of an auxiliary input signal,
*
use MsysInquire() with M_IO_STATUS . The state of auxiliary input signal
USERBIT0 (M_AUX_IO0) can also generate an interrupt; to do so, use
*
MsysControl() with M_IO_INTERRUPT_STATE and then use
*
MsysHookFunction() with M_IO_CHANGE to hook a function to this event
(that is, to set up an event handler).
For information on the electrical specifications of auxiliary signals, see the
Electrical specifications section, in Appendix B: Technical information.
*. As of MIL 10.