Hello,
Command : ./osmocon -m c123xor -p /dev/ttyUSB1 -s /tmp/osmocom l2 -c target/firmware/board/compal_e88/trx.highram.bin
Before running a base station, please at least learn how to access the filesystem in UNIX based operating systems. Apparently, there is directory 'target' in 'src/host/osmocon'. It's in 'src/', so either run osmocon from 'src', or use '../../target/firmware/board/compal_e88/trx.highram.bin'.
For more details, see: https://osmocom.org/projects/baseband/wiki/CalypsoBTS.
With best regards, Vadim Yanitskiy.