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Visitor II
February 6, 2004
Question

ST62T65 problem with ports and interrupts

  • February 6, 2004
  • 2 replies
  • 829 views
Posted on February 06, 2004 at 08:23

ST62T65 problem with ports and interrupts

    This topic has been closed for replies.

    2 replies

    Visitor II
    February 5, 2004
    Posted on February 05, 2004 at 14:16

    I work with 4 interrupts simltaneously: NMI

    AR Timer

    A/D Converter

    TIMER

    My ports have next configuration:

    DDRA 11110000 DDRB 11111111 DDRC 00000010

    ORA 11110010 ORB 00111111 ORC 00000010

    DRA 11110110 DRB 11111111 DRC 00000011

    All interrupt works in real time.

    My problem is:

    When I reconfigure outputs of port B in Timer (or A/D converter) interrupt, then interrupt of AR timer is not periodical.

    All the time I have in ARCP register the same value.

    My AR Timer works in auto-reload mode, and makes compare interrupt.

    What I must do, to interrupt of AR Timer was periodical, and independent from reconfiguration port B in vector 4 interrupt.
    Visitor II
    February 6, 2004
    Posted on February 06, 2004 at 08:23

    When you configure the timer intrerrupt, this makes the timer interrupt to occur after the particular time. Also at the same time you are also enabling ARtimer interrupt.

    The ARtimer interrupt in this case in not periodical. This is due to the fact that if the ARtimer interrupt occur when the controller is executing Timer Interrupt service routine, then first the timer interrupt routine will get executed and after completing the Timer ISR, the control will go to ARTimer routine or any other ISR depending on the priority of the interrupt.