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Re: VAXstation 4000/90 help

On 2010-11-29 03:32, John Klos wrote:
Hum. I'd check the switch for a bad connection or something then. If
the LEDs are changing, there should be output on the console.

The LEDs only change once, and only once again if the halt button is

I believe that is to be expected.
Or did I missunderstand something...? I thought you said they did a "countdown"?

If not, then it's either directed to the wrong console, or else you
have a broken serial port.
(I assume you are using the right port on the VAX, that your cable is
ok, and that you have a terminal connected that aren't messing you up
with some weird opinions (or a computer with some program connecting
you to a serial port).

It's the same setup I use for one of my 4000/60, so I know the machine
I'm running cu on is fine and I know the cable is good.

That is good to know.

There is a lot of serial port debugging that can be done, but it is so
much depending on what you observe, and so on, that it's hard to write
a general checkup.

Part of the problem is that I don't get anything at all on the serial...

So I'd break out the oscilloscope and check the wires... You should have a minus on the Tx from the VAX, which should flutter when it transmits. Also check the DTR.


Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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