topic Re: How to disable watchdog in init phase for FS6500 SBC chip? in Power Management

How to disable watchdog in init phase for FS6500 SBC chip?

chetan_lonshika — Fri, 05 Oct 2018 06:49:36 GMT

I am using SBC FS6500 chip. I want to disable sbc watchdog in bootloader and application will initialize and trigger it. First I established SPI communication between SBC and microcontroller then I tried to set watchdog window to (0000) initially in order to disable it in init phase as per datasheet but its not working and reset happens.

Re: How to disable watchdog in init phase for FS6500 SBC chip?

TomasVaverka — Mon, 08 Oct 2018 12:56:41 GMT

Hi Chetan,

The watchdog disable (WD_WINDOW_3:0 = 0b0000) is effective only when the INIT_FS phase is closed, so it requires at least one good watchdog refresh (0x4D when using a default LFSR value of 0xB2) within the 256 ms of the INIT_FS timeout.

Best regards,

Tomas

Re: How to disable watchdog in init phase for FS6500 SBC chip?

chetan_lonshika — Wed, 10 Oct 2018 04:59:32 GMT

Its working, Thank you

Re: How to disable watchdog in init phase for FS6500 SBC chip?

ramanjineyuluth — Tue, 05 Feb 2019 05:43:50 GMT

Hi,

After disabling the watchdog, PMIC does not wakes up.

How to send good watchdog refresh to exit INIT_FS.

I used below code for good watchdog refresh and disabled watchdog.

/* Performs the watchdog refresh. */
TxDataWithoutCrc[0] = WR_FS_WD_ANSWER | 0x5AB2; /* Normal Watchdog - Default WD_SEED value */
/* Calculate the 8-bit CRC with POLYNOMIAL 0x1D */
crc = CalculateCRC8(TxDataWithoutCrc);
TxData[0] = (TxDataWithoutCrc[0] << 8) | crc;
SpiTxWord(TxData);

/* Disable the PMIC Watchdog */
TxDataWithoutCrc[0] = WR_FS_WD_WINDOW | 0x0200;/* 0=DISABLE, 2=open/close window 50%, 00=Wathcdog recovery disable */
/* Calculate the 8-bit CRC with POLYNOMIAL 0x1D */
crc = CalculateCRC8(TxDataWithoutCrc);
TxData[0] = (TxDataWithoutCrc[0] << 8) | crc;
SpiTxWord(TxData);

Can you please help me, how to disable the watchdog.

Thanks in advance.

Thanks,

Ram.

Re: How to disable watchdog in init phase for FS6500 SBC chip?

ramanjineyuluth — Tue, 05 Feb 2019 07:02:58 GMT

Hi Tomas,

After disabling the watchdog, PMIC does not wakes up.

How to send good watchdog refresh to exit INIT_FS.

I used below code for good watchdog refresh and disabled watchdog.

Can you please help me, how to disable the watchdog.

Thanks in advance.