isns10@ms3.UUCP (Russ Brandon) (11/12/87)
I need some help getting my PC to recognize a third serial port
(addressed as com3). I bought a Xerox 6064 PC-XT compatible in
May. Since then I have been making gradual upgrades to it. After
consulting with the Xerox/Diablo support center in Texas, I was
informed that the 6064 could support three serial ports ( com1 -
com3 ), as long as the ports added could be addressed as com2 and
com3. The serial port originally installed in the computer is
"hardwired" as com1. I reviewed the documentation that came with
the system, and it also clearly states that the SOFTWARE will
support three serial ports.
I purchased an Amazing Things internal modem which can be
addressed as com1 - com4. I installed it as com2 and it worked
fine. I recently ordered an AST SIXPAKPLUS with 384k of memory, a
parallel port, a serial port, and a clock/calendar. I have
installed the board according to the documentation. The memory,
the parallel port and the clock work fine. My problem is that I
can not get the computer to recognize three serial ports. Since
the AST SIXPAK's serial port is only addressable as com1 or com2,
I configured it to com2. My modem is capable of being configured
as com1 - com4. I configured the modem to com3. When I run the
system diagnostics, it only finds two serial ports. Both the modem
and the SixPak work fine addressed as com2.
I have used the following configurations in my system with the
same results, it only recognizes com1 and com2.
com1 IRQ4 - Static -
com2 IRQ3 - AST's configuration -
com3 IRQ4 and IRQ5 - Modem configuration -
Even though the diagnostics don't find the third serial port, both
XTALK XVI and BITCOM can access the modem and dial out. But I
never get any response back, so I don't know if the connection is
established. I think there is a connection but my system can not
handle communications through the third serial port. I can
terminate the connection using the appropriate escape sequences,
so the system is not hanging.
To make a long story short, I have a Xerox 6064 PC-XT compatible
with Phoenix BIOS running 3.10 MS-DOS, release 2.0, ver 88. I have
not been able to determine the rev level of the BIOS. I have an
AST SIXPAKPLUS with 384k of memory, a serial and parallel port,
and a clock/calendar, and an Amazing Things modem. The
documentation for the system indicates that the software can
handle three serial ports. The serial port that was originally
installed is addressed as com1. The SIXPAK's serial port is
addressed as com2, and the modem is addressed as com3. The system
doesn't recognize the third serial port.
1) Is this a limitation of the hardware?
2) Is this a problem with the configuration of the system's
hardware or software? Is there a DIP switch or a parameter that is
not set correctly?
3) Is there a way to get the system to recognize the third serial
port, either through modifying hardware or software?
I would greatly appreciate an answer to this problem. I will be
purchasing a hard disk drive soon, and would like to know if the
system has limitations that will prevent me from configuring it
the way I would like. I'd rather spend a little more money and
have a usable system, then spend money and have a pile of nice
hardware.
P.S. I contacted The Xerox support center on this and they
couldn't help me. They have no knowledge of anyone ever trying to
add more then one serial port to the 6064.
--
Russell Brandon UUCP: ...!seismo!vrdxhq!ms3!RSB
US MAIL: c/o ISN Corp.
1235 Jefferson Davis Hwy Suite 220
Arlington, Va. 22202