I fixed the UART assignment for ttyS0 with
# setserial /dev/ttyS0 UART 16550A
and now my modem's TR signal is high as desired. My question, am I condemned to manually editing the grub.conf file after every kernel update or is their a way to configure the system so that I get access to ttyS0 with the grub entries as distributed via yum?
Sincerely,