Hi,
I have an application running, with MCUBOOT, on a custom nRF52832 hardware (NCS v2.2.0). The problem is that a device connected to the NFC pins cannot tolerate a high output level on those pins. What happens is that, before the application is started, and I can make sure that those pins are set to a low level, the bootloader creates a high pulse on them. I cannot figure out on how to prevent this.
So, the _defconfig file of the custom board sets CONFIG_NFCT_PINS_AS_GPIOS=y. In addition its .dts file utilizes &pwm0 and &pwm1 which are, in turn, mapped to the NFC pins (i.e. P.0.09 & P0.10) in the .dtsi file. If I change the mapping to some unused pins the problem disappears but this is, obviously, not as solution as I need to output PWM on the NFC pins in my application.
My thinking is that I either need to make sure that the bootloaders .dts file (where is it ?) holds the NFC pins low during the whole boot process and/or that I let the bootloader map &pwm0 and &pwm1 to some other “safe” pins and then, using “dynamic pin control”, let the application re-map them to the NFC pins.
Any advice on how to resolve this would be most appreciated.
Cheers
Eric
