I want to disable the JTAG that I can turn off the Pullup.
Not sure I understand the question/context.
You should be able to disable the JTAG/SWD in a variety of ways, including options byte (protection levels), reconfiguring the GPIO/AF states.
I'm looking for a function in the HAL Library that I can disable the JTAG because I have to turn off the Pullup on the PA15, I'm using the STM32L476RG.
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