Hi guys,
I use the KL03 and I'll unset the BOOTPIN_OPT flag of the FTFA_FOPT register. I'd like to make the user able to short GND and the boot pin during reset to trigger the bootloader as a safety firmware upgrade method.
My question is whether I need to use a pull-up resistor for the boot pin, or is the internal pull-up sufficient.
Thanks in advance!
- Laci
Solved! Go to Solution.
Hi Laci,
Please take care, the BOOTCFG0 pin is also the /NMI pin, from the /NMI pin recommend design, it is better to add the external 4.7K to 10K pull up resistor.
http://cache.nxp.com/assets/documents/data/en/user-guides/KLQRUG.pdf?fsrch=1&sr=1&pageNum=1
Page 23, chapter 2.1.3.4.1 RESET_b and NMI_b.
The MCU can work if you don't add the external pull up, but for good design, I suggest you to add the external 4.7k to 10K pull up resistor.
Wish it helps you!
Have a great day,
Kerry
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Hi Laci,
Please take care, the BOOTCFG0 pin is also the /NMI pin, from the /NMI pin recommend design, it is better to add the external 4.7K to 10K pull up resistor.
http://cache.nxp.com/assets/documents/data/en/user-guides/KLQRUG.pdf?fsrch=1&sr=1&pageNum=1
Page 23, chapter 2.1.3.4.1 RESET_b and NMI_b.
The MCU can work if you don't add the external pull up, but for good design, I suggest you to add the external 4.7k to 10K pull up resistor.
Wish it helps you!
Have a great day,
Kerry
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------
Got it! Thank you, Kerry!