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df1061b6fa
It is official open-source release, prepared for TI by RedHat. Old "mspgcc" ports, which were made obsolete almost year ago, are marked as DEPRECATED.
33 lines
1.3 KiB
Text
33 lines
1.3 KiB
Text
Watchdog Timers and Init Code
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A change has been made to the start-up code: the code to
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disable the watchdog timer has been removed. The code was
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in the start-up sequence because it was found that for some
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large applications the watchdog timer would trigger whilst
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the start-up was happening - ie before main() was reached.
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The problem with the disabling code was that the address of
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the watchdog timer was hard-coded in the instruction
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sequence, which meant that it did not work on MCUs that
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used a different address. Rather than try to provide some
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complicated, MCU specific, mechanism for disabling the timer
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during start-up it was decided to simply remove the code
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instead. For most applications this should suffice. If
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however an application does need to disable the watchdog
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timer during start-up, it can add this function to its code
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base:
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#include <msp430.h>
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static void __attribute__((naked, section(".crt_0042"), used))
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disable_watchdog (void)
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{
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WDTCTL = WDTPW | WDTHOLD;
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}
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Note - this method can be used to insert *any* commands
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into the start-up sequence, not just watchdog timer
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disabling code. Also if the number in .crt_0042 is
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reduced, the code will execute earlier in the start-up
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sequence. If it is increased it will execute later in
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the start-up sequence.
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