On Sat, 22 Feb 2003 23:52:41, Alexandre Kazantsev writes: >Is there anything in Palm OS 5 running in background and interrupting >a foreground application? ... >My application runs great in Palm OS 4.x doing data acquisition >synchronously at high speed. ... What about... Palm OS 5?
Under OS 5, sampled sound callbacks seem to run in their own separate thread (on the m550). Even handheld's running OS 4 with CPU interrupts disabled won't be completely synchronous systems. Memory contention from display refresh may still cause some instruction fetch wait-state jitter. On OS 5 systems, there may also be some instruction timing variations due to initial cache fills and then potential cache line contention between PACE and the emulated 68k code. One alternative under OS 5 is to the data acquisition by running armlet code in asynchronous polling loops (perhaps using one of the high resolution counters). OS 5 armlet code is fast enough that this technique may have better performance than PACE emulated 68k code running "synchronous" timing loops. IMHO. YMMV. Ron Nicholson HotPaw Productions <http://www.hotpaw.com/rhn/hotpaw> -- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/
