some instructions from Alan VK2ZIW for configuring serial port to be able to run FPP software to program the PRM80:


Notes on running PRM80 FPP programs on Linux
============================================
Fedora 23 x86_64 on ASRock QC5000 system (Low Power AMD Kabini)
with FTDI Serial USB dongle ID 0403:6001, it's TTL to the radio

Radio: PRM80L S E0
     PRM8025 - 9502 810 10869

Reason: Conversion to 6m with VK3SMB's eprom, subtracts 20MHz
from the eeprom stored channel frequency, 68MHz becomes 48MHz.

The FPP DOS program does horrible things with the USART so
run "dosbox" with a network serial port. Use "netcat" (nc)
to connect to the FTDI serial port.

Edit ~/.dosbox/dosbox-0.74.conf
Setup the DosBox serial port:

serial1=nullmodem port:5000 transparent:1 rxdelay:1

After your "MOUNT" command for C: add:
C:
cd prm80pmr
bin\prm80pmr

Save your "dosbox-0.74.conf" file.

Setup the serial port, "stty raw" - most important
as you don't want any control characters interpreted.
"clocal" to ignore Carrier Detect. 4800 baud, 8bit, no parity.

#============ shell script rundb ==================
sleep 2 < /dev/ttyUSB0 &
stty raw < /dev/ttyUSB0
stty 4800 clocal cs8 < /dev/ttyUSB0
sleep 1
dosbox &
sleep 2
 nc localhost 5000  < /dev/ttyUSB0 > /dev/ttyUSB0
#============== script end ==============