SBC happens reset after MCU softrese

[aaron0312]

I am using SBC FS6500 chip.

currently, SBC will happen reset after MCU softreset(softreset: means SBC can't turn off power because SBC supply power to MCU).

is any way to fix SBC reset after MCU softreset?

Thanks a lot

@FS6500

[TomasVaverka · Accepted solution]

Hello Aaron,

I am not sure I fully understand your question.

Does soft reset assert your MCU Reset pin to low?

If so, the MCU Reset pin should connect SBC RSTB pin for watchdog synchronization.

If not, the MCU can request a RSTB_LOW from SBC to assert RSTB pin for software synchronization.

Best regards,

Tomas

[aaron0312]

Hi Tomas,

Thank you for answering.

you: Does soft reset assert your MCU Reset pin to low?

-> Yes, Reset pin will be low, but why SBC watchdog not synchronize?

you: If not, the MCU can request a RSTB_LOW from SBC to assert RSTB pin for software synchronization.

-> I did request "SF_OUTPUT_REQUEST" to low, but SBC will cut MCU power for a short time, and MCU RAM data will be gone.

Thanks

[cuongnguyenvan]

Hello Aaron,

I remember that you can set the delay of RST_B to 10ms in the INIT_FSSM (It's default of sbc)
Other way, It's complex than.
You can use the Wdg_Window enable, and raise RSTB reaction if wdg trigger fail.

The RSTB will assert low after a few times Wdg Window duration( can configure)
However, your application always synchronous timing between SBC and MCU.( suggestion: Begining user should set the wdg window disable and then if you want to softreset, please change wdg window to Enable and it will raise reset after few window time.
you can configure time in register WD_WINDOW.

Regards

Cuong