what‘s problem about fs26 debug pin connect VBOS directly?

[yang_yang3920]

debug pin connect VBOS directly will cause fs26 enter OTP mode permanently , can't exit debug by sending spi exit-debug command, correct ? where can find this proof in fs26 date sheet?

[JozefKozon]

Dear Yang_Yang3920,

to connect the DEBUG pin to VBOS will not set the FS26 to OTP mode. Please refer to the Table 259. for conditions to enter Normal mode, OTP mode and Debug mode in the FS26 full datasheet. For exit OTP mode, please refer to the section 21.1 and Figure 76.. 

The FS26 full datasheet is available in the FS26 product page, under the Secure section.

With Best Regards,

Jozef

[yang_yang3920]

is there any problem for my electronic schematic above ,that's fs26 debug pin connect VBOS directly. current problem is that can't exit debug by sending spi exit-debug command.

[JozefKozon]

Dear Yang_Yang3920,

I suspect that your FS26 is not in Debug mode. To enter Debug or OTP mode, there are voltage and timing requirements for applying voltages. Please refer to the section 21. and to the Table 259. in the FS26 full datasheet for requirements and timings. 

There is a bit in FS26 registers to confirm if the FS26 is in DEBUG mode. Please refer to the Table 105. Please check this bit if the FS26 is in DEBUG mode.

With Best Regards,

Jozef

[yang_yang3920]

1. need external event "Debug pin = GND" to trigger fs26 exit OTP mode when fs26 start up into OTP mode .you can see OTP mode flowchart.
2. need external event "2.5 V < VDEBUG < 6 V" to trigger fs26 exit debug mode when fs26 start up into debug mode .you can see Debug mode flowchart .
but for my electronical schematic above , fs26 debug pin connect VBOS directly, that's limit fs26 can only be one of these two modes , before not sending spi exit-debug command. correct?

that's means after fs26 startup finish in my electronical schematic, no above mentioned external event to trigger fs26 make flow State Machine  to run continuous.

[JozefKozon]

Dear Yang_Yang3920,

please confirm if you have access to the FS26 full datasheet. Please check the UM11503 attached. This might give you hints about the FS26, if you haven't the FS26 full datasheet. However without the full datasheet it would be very difficult to work with the FS26. I cannot answer any questions, which answers are not available in public documents. I can only point you where the information are located in the confidential documents. For the DEBUG function, voltage levels and timings please refer to the section 21. in the full FS26 datasheet. 

In this section are also information how to exit the Debug and OTP modes. 

With Best Regards,

Jozef