MSP430F6779A: About stop watchdog during start up in function _system_pre_init

TinK

as we have use ccs IDE with low level process initial function _system_pre_init that stop watchdog below.

#1 Stop watchdog in _system_pre_init

int system_pre_init(void)
{
    /* Insert your low-level initializations here */
    __disable_interrupt();
    WDTCTL = WDTPW+WDTHOLD; // Hold watchdog

    return 1;
}

if we change to start watchdog interval 1 second. Is it better?

#2 Start watchdog 1 second in _system_pre_init

#define DEF_WDTCTL_START_1S (WDTPW + WDTSSEL_1 + WDTCNTCL + WDTIS_4)

int system_pre_init(void)
{
    /* Insert your low-level initializations here */
    __disable_interrupt();
    WDTCTL = DEF_WDTCTL_START_1S; // start watchdog interval 1s

    return 1;
}

If in this state in _system_pre_init, the power supply in not stable yet (the Vsys can drop below 1.8 V).
Can we enable watchdog in this time?

over 2 years ago

0 Xiaodong LI over 2 years ago

TI__Mastermind 25875 points

Hi Tink

May I know which board and which ccs version customer used?

I will check in detailed soon

Thanks

0 TinK over 2 years ago in reply to Xiaodong LI

Intellectual 815 points

Hi Xiaodong LI,

IDE version: Code Composer Studio 10.1.1.00004
Compiler version: TI V20.2.1.LTS

It is our customized board utilized the Energy Measurement Design Center version 1_30_00_00.

0 Xiaodong LI over 2 years ago in reply to TinK

TI__Mastermind 25875 points

Hi Tink

I recommend you don't change the code on low level process initial function _system_pre_init.

you can Stop WDT at the start of main function as the code example https://www.ti.com/tool/download/SLAC648

Thanks

0 TinK over 2 years ago in reply to Xiaodong LI

Intellectual 815 points

Hi,

Thank you for the information. If Watchdog is disabled in the function _system_pre_init Is there a risk that the MCU might get stuck at this time when something abnormal happens (e.g. DVCC power supply unstable, noise ..)?

Why isn't Watchdog enabled in? _system_pre_ini

0 Xiaodong LI over 2 years ago in reply to TinK

TI__Mastermind 25875 points

Hi Tink

Watchdog is run (not stop) as the initial setting. The interval time is 1s at 32.768Hz as the initial setting

this time is enough for function _system_pre_init running.

change function _system_pre_init is OK but it is not recommended.

I recommended operate WDT on the main loop.

Thanks

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MSP430F6779A: About stop watchdog during start up in function _system_pre_init