Hi!
I have the following problem: a touch screen is connected with a rs232 to usb adapter (ftdi or prolific) to a
4 port usb hub which is connected to the otg port of a beagle board. The touch screen sends with 9600 baud
(8N1) packets of 5 bytes which contain touch state and coordinates, but only when the screen is touched (3M EXII
Protocol). When released a last packet follows where the touch state is off. In principle everything works, but when I touch
the screen (which then starts to send packets) the system seems to freeze for 300 to 400 ms. Therefore there is a latency
until a toch is registered. When releasing a touch this is quite fast, i.e. no freezing. Per frame there is only one read
call to the serial port, the screen is rendered with opengl es 2.0. But the problem is also visible if there is only debug
output and no rendering at all (console based test program). The same test program runs ok on Mac OS.
Do you have any idea where this may come from? Which information can I provide?
Thanks,
Jochen
