currently, I am trying to stabilize system behavior within a high-speed
robot control done on a standard PC under QNX Neutrino (currently v6.2.). It
seems to be connected with sporadic mouse movements and window refreshments
on the photon screen. Here is the scene:
Upon reception of a cyclic, hardware-generated interrupt (exactly every 1 ms
from the communication system), some calculations are made in a high
priority thread in order to set the contents of an outgoing data telegram.
After composition, the data telegram is broadcasted on the communication
bus. The external components receiving the broadcast, each evaluate the data
and send back an answer telegram. For some components, it is necessary that
the time intervals between the incoming data telegrams are always the same
(there is a small tolerable jitter).
When I move the mouse pointer on the PC the open windows on the photon
screen are activated and deactivated. This internally leads to the behaviour
that the time between reception of an interrupt and the actual appearance of
the data telegram on the communication bus varies so much, that the
sensitive external components run out of synchronisation.
Here are some questions:
A. Is it possible to set the priorities of these automatic mouse and screen
manipulations to a low priority, so that the control procedure is not
B. Is it possible to switch off mouse and keyboard activities by software?
C. Are there maybe some other hidden places for configuration of these
effects except the BIOS settings? In the BIOS I have already disabled
everything that looked like having something to do with mouse and screen
I would be happy if someone could help me with this.