Linux-Hams archive - July 1997: KPC3+ problem and serial chip

KPC3+ problem and serial chip

Albert Woodhull (terhi.victor@logonet.com)
Thu, 3 Jul 1997 05:41:23 GMT


A while back I asked for help on a problem I have had with the KPC3-Plus
TNC (but not the older KPC3) in KISS mode. I still haven't solved that
one, nor has Kantronics answered my query to them, but I received a reply
that has me wondering about another possible problem.

One writer suggested I would have a problem with either Windows or Linux
and a KISS TNC if I do not have a 16550AF serial interface chip. I have
noticed on my listen screen that sometimes I get packets that aare missing
a character or two. The characters are not garbage, they seem to have
dropped out. This would be consistent with a serial buffer problem.
This is different from the problem I had earlier, although I suppose it
could be related -- I suppose there are bytes that could cause something
that looks like a wild buffer overrun problem if they dropped out.

My Linux dmesg and an old Microsoft MSD tell me only that I have a 16550A.
Question number one is, can someone confirm that an ordinary 16550A is not
good enough? Question number 2 is, can the Linux kernel detect the difference
between the A and the AF (I am now using a 2.0.30 kernel)? Question 3 is,
is there anything I can tweak in the kernel code to compensate?

The computer in question is a Compaq Armada 1120. It is a reasonably current
model (purchased Jan 97). I thought the serial port chip question was one
that had been resolved quite a while ago, should I be concerned with such
a new computer? It is a laptop, and I am not sure how easy it would be to
look inside it, nor am I hopeful that I would find a socketed and replaceable
serial chip if I did so.

73, Al N1AW / YN1ASW

--------------------------------------------------------
Albert S. Woodhull
mpkxg@mailit.tunk.net
bmasjkdq@toronto.ca
zwid@fremantlemedia.net (solamente dentro de la UNAN)
srozrecg@maplenet.net