Code:
Define ADC_BITS 4 ' Set number of bits in result
from manual
You may set ADC_BITS to values 8-16, but in reality the result will either be 8-bits or the maximum precision available (10-bits, in most cases).
Code:
DEBUG #adval
could send 1 to 5 ascii chrs for a word value {adc value 1 to 4 chrs }

Code:
DEBUGIN 1000,timeout,[adval]
how is that meant to work ? you will also discover debug sends/receives bytes not words

DEBUGIN 1000,timeout,[dec adval]
might have a chance.

simplistic async coms like this is seldom reliable, especially if the receiver has other tasks to perform other
than sitting there waiting for a transmission.

packetizing data in stx/etx codes and preferably with crc too is a better choice