Post your code so we can determine what the issue is.
If the UART is configured for SCB0 , then seems like it is better to configure the ADC pins onto the SCB1 pins.
P0,P1,p3 all uses SCB 0 , but is the routing for these pins , the same??
The problem is with your ADC ISR. Go to ADC configuration and in channels tab disable saturation option for channel 0. Then everything is working fine.
The saturation option was causing the problem. This is from ADC component datasheet:
This option allows you to enable an interrupt from any channel where the result is saturated from either a conversion result of 0x0000 or the highest value for the given resolution."
So when you enabled saturation and the pin was connected to ground, the interrupt was getting triggered continuously. So the code was getting stuck at ADC ISR. This affected your UART communication. Once that option is disabled, everything is working fine.
Thank you for the valuable reply..