zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) (02/13/89)
I have problems with the machine locking up when I install a 16550A on a uport 3.0e system and enable the fifo. Has anyone been using one successfully? -- Jon Zeeff zeeff@b-tech.ann-arbor.mi.us Ann Arbor, MI mailrus!b-tech!zeeff
bill@twwells.uucp (T. William Wells) (02/13/89)
In article <5111@b-tech.ann-arbor.mi.us> zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) writes:
: I have problems with the machine locking up when I install a 16550A
: on a uport 3.0e system and enable the fifo.
:
: Has anyone been using one successfully?
Yes.
I enable it by writing 0xC9 to I/O port 0x3FA when I boot. I have
the standard driver. BTW, have those poeple who had 16550A drivers in
beta released them yet?
I've always had problems with my modem locking up, in that the modem
transmits to the system but the system doesn't hear it. This has not
changed since I installed the 16550A. However, this has never brought
my system to a halt; all it does is require me to reboot if I want my
modem to work correctly. I'm almost certain that this is something
wrong with my I/O card.
---
Bill
{ uunet!proxftl | novavax } !twwells!billbob@obiwan.UUCP (Bob Willcox) (02/13/89)
In article <5111@b-tech.ann-arbor.mi.us> zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) writes: >I have problems with the machine locking up when I install a 16550A >on a uport 3.0e system and enable the fifo. > >Has anyone been using one successfully? I too have had my system lock up when I enable the fifo on my 16550A (using the igloopatch). This is on a 286 box running V/AT ver 2.4. -- Bob Willcox ...!{rutgers|ames}!cs.utexas.edu!romp!obiwan!bob Phone: 512 258-4224
learn@igloo.Scum.COM (william vajk) (02/13/89)
In article <5111@b-tech.ann-arbor.mi.us> Jon Zeeff writes: > I have problems with the machine locking up when I install a 16550A > on a uport 3.0e system and enable the fifo. > Has anyone been using one successfully? Runs flawlessly on 286 both 2.3 and 2.4. The width is set to 8. I'm mailing the 286 code to you as a working 286 example. Anyone else attempting this is welcome to another copy via e-mail. Bill Vajk | A person of quality is never intimidated. learn@igloo |
sl@van-bc.UUCP (pri=-10 Stuart Lynne) (02/14/89)
In article <379@twwells.uucp> bill@twwells.UUCP (T. William Wells) writes: >In article <5111@b-tech.ann-arbor.mi.us> zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) writes: >I've always had problems with my modem locking up, in that the modem >transmits to the system but the system doesn't hear it. This has not >changed since I installed the 16550A. However, this has never brought >my system to a halt; all it does is require me to reboot if I want my >modem to work correctly. I'm almost certain that this is something >wrong with my I/O card. Sounds like you're driver isn't servicing interrupts properly. If the interrupt service routine doesn't completely clear all sources of the interrupt then you will never get another successful interrupt for that interrupt line. This is a function of the PIC, it is level triggerred; and if you never bring the level down it cannot see someone else bringing it high. -- Stuart.Lynne@wimsey.bc.ca {ubc-cs,uunet}!van-bc!sl Vancouver,BC,604-937-7532
zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) (02/14/89)
>: I have problems with the machine locking up when I install a 16550A >: on a uport 3.0e system and enable the fifo. >Yes. >I enable it by writing 0xC9 to I/O port 0x3FA when I boot. I have >the standard driver. This is what I do and after some time (like overnight), I find that the process using the port is hung. If I kill it and start another, the entire machine locks up. It sounds like a driver problem to me, although I suppose it could be caused by some interaction with my serial card or the 16550A I have. BTW, have those poeple who had 16550A drivers in >beta released them yet? Good question. >I've always had problems with my modem locking up, in that the modem >transmits to the system but the system doesn't hear it. This has not >changed since I installed the 16550A. However, this has never brought I've seen this problem under Dos Merge, but never from Unix. I did find that the 16550A cured all the problems I had with using the serial ports at 2400 bps under Dos Merge. -- Jon Zeeff zeeff@b-tech.ann-arbor.mi.us Ann Arbor, MI mailrus!b-tech!zeeff
rick@pcrat.UUCP (Rick Richardson) (02/15/89)
In article <2226@van-bc.UUCP> sl@van-bc.UUCP (pri=-10 Stuart Lynne) writes: > >This is a function of the PIC, it is level triggerred; and if you never >bring the level down it cannot see someone else bringing it high. Small correction, it is being used in *edge triggered* triggered mode; and if you never bring the level down it cannot see someone else bringing it high. If the PIC had been programmed level trig, then not servicing the interrupt would be real obvious - you'd spend all day going in and out of the ISR. -- Rick Richardson | JetRoff "di"-troff to LaserJet Postprocessor|uunet!pcrat!dry2 PC Research,Inc.| Mail: uunet!pcrat!jetroff; For anon uucp do:|for Dhrystone 2 uunet!pcrat!rick| uucp jetroff!~jetuucp/file_list ~nuucp/. |submission forms. jetroff Wk2200-0300,Sa,Su ACU {2400,PEP} 12013898963 "" \d\r\d ogin: jetuucp
bill@twwells.uucp (T. William Wells) (02/16/89)
In article <5113@b-tech.ann-arbor.mi.us> zeeff@b-tech.ann-arbor.mi.us (Jon Zeeff) writes:
: >: I have problems with the machine locking up when I install a 16550A
: >: on a uport 3.0e system and enable the fifo.
: >Yes.
:
: >I enable it by writing 0xC9 to I/O port 0x3FA when I boot. I have
: >the standard driver.
:
: This is what I do and after some time (like overnight), I find that the
: process using the port is hung. If I kill it and start another, the
: entire machine locks up. It sounds like a driver problem to me, although
: I suppose it could be caused by some interaction with my serial card or
: the 16550A I have.
Here's what I've figured. First, certain of my problems are due to
flaky hardware. For example, I find that most mornings recently my
machine has crashed, as in totally locked up, no messages, nothing.
It is invariably midway through the expires that I do each morning.
This, plus crashes due to NMI's, is why I think there is a hardware
problem (my money is on something heat related or mechanical). So,
after discounting these, the serial problems I have are these:
1) Sometimes the serial port locks up. When I look at the serial
chip, all seems well with it, except that data coming from the
modem doesn't appear in the receive register. I tried sending
data to the modem when it should have been in command mode
(after a power cycle) and then reading the recieve register
directly. Nothing. So, if I did that correctly, then the idea,
expressed by Stuart Lynne, that my driver is losing interrupts,
is not correct (or at least not relevant); however, the next
time that this happens I'll go check out the state of the
interrupt chip. (Oops! I'll have to go get a manual, I think
mine have disappeared....)
2) There is a bug in the Trailblazer firmware (confirmed by
Telebit) that causes it to fail to deal properly with a dropped
DTR around when it is hanging up the phone. This has, for me,
the irritating effect of preventing it from reloading the modem
parameters at the end of a call. Right now, I partly solve that
problem by a using a wrapper about uucico to reopen the tty
line and force a parameter reload.
3) It does not appear to be possible to change the interface speed
when the modem is off-hook. This is a problem for me because,
when I tried to use flow control instead of a variable interface
speed it didn't work. So, I'm using varying interface speeds.
This is a problem when, for whatever reason, the other system
won't let go of the line. Then one has to figure out what speed
the modem is operating at in order to get its attention or one
must do something drastic like pulling the plug. (I have an
unconfirmed suspicion that dropping DTR doesn't always force a
hangup either, but I'll have to check that out later.)
4) Sometimes the getty and whoever is calling will get into some
kind of ping-pong loop. The worst I've seen there was when I
started loosing keyboard interrupts; I unplugged the modem
instantly, thus probably preventing a system crash.
It occured to me, as I wrote the above, that here could be
where your problem is: there used to be a UNIX bug wherein if
all the clists were used up the system would crash. Suppose that
your modem got into one of those loops and ran out of clists....
However, I should say that, by and large, my current setup works.
These problems, other than the first, tend to fix themselves; in
fact, only the last mentioned problem would seem to be a candidate
for a crash-causer.
: >BTW, have those poeple who had 16550A drivers in
: >beta released them yet?
:
: Good question.
I did get one answer to my question; he say's that he's been busy.
(Where did I hear that last? :-)
---
Bill
{ uunet!proxftl | novavax } !twwells!bill