I am trying to connect an ultrasonic sensor to a QNX PC104 system and need
some help.
I have to set a line high on the sensor and start a timer. When another line
on the sensor goes high I need to stop the timer. If the timer reaches 30mS
I also want to stop it.
I want the timer to be as accurate as possible, so I think I need some kind
of interrupt to stop the timer. The board I have has several RS232 ports, a
Printer Port, USB, PS2, …
What QNX timer can I use to give 30uS, or better, resolution?
What I/O line can I connect to which can be used to trigger an interrupt to
stop the timer?
Any help appreciated. (I would consider external HW)
Hi Liam,
I use an external ultrasonic system that I communicate with through the
serial port. It gives me distance from approx. 2.5 inches to 40 or more
inches. Ths board can be tailored to work out to greater distances. The
board and sensor is about $200.00 for our custom version although less
expensive and packaged ones exits. see http://www.senix.com
Walt
I am trying to connect an ultrasonic sensor to a QNX PC104 system and need
some help.
I have to set a line high on the sensor and start a timer. When another
line
on the sensor goes high I need to stop the timer. If the timer reaches
30mS
I also want to stop it.
I want the timer to be as accurate as possible, so I think I need some
kind
of interrupt to stop the timer. The board I have has several RS232 ports,
a
Printer Port, USB, PS2, …
What QNX timer can I use to give 30uS, or better, resolution?
What I/O line can I connect to which can be used to trigger an interrupt
to
stop the timer?
Any help appreciated. (I would consider external HW)