Re: Mount does not stop Update

Roland Christen

There are two sets of software, the one in the keypad and the one in the
servo controller. These two are separate from each other and stand alone from each
other. Version 4.12 is the keypad software, but this has no effect whatsoever
on the action between the servo controller and other external command
software such as Pulse Guide and TheSky6.

If the servo controller is not responding to external commands, it might be
because it is being overloaded with requests (such as position requests from
The Sky6). This was a weakness in very early software and was fixed in later
versions of the servo control software (not to be confused with the Keypad V4.12
software). I asked Mike, our development engineer, and here is what he said:

Very early versions of firmware occasionally dropped com port characters if
the com ports kept the mount very busy. I do not recall which version
introduced the fixes. But I recall dealing with Bob Denny, Ray Gralak, and a couple
others on this. Bob e-mailed us "Port Mon" sessions that showed dropped
commands. We also replicated issues with the mount dropping move/stop commands from
the keypad until the software was fixed. The reason the keypad is affected
is because there were brief periods of time that the controller was busy
processing commands from other ports while the interrupts were disabled. If the
controller is "out to lunch" longer than two characters (2.3mS), one character
could be ignored, which could make the entire command unrecognizable and
therefore lost.

Marj might have records that show what firmware versions introduces the fixes
to these problems, we recently discussed revision history of the world.
Otherwise I can look it up later tonight.

If he is ordering an E1 chip, he must have a GTOCP2. I do not recall these
problems with the GTOCP2, but a new chip is the next logical step.


Therefore it appears that your mount has some very old version of servo
control software which had problems handling more than 1 input from external
programs. We have basically solved this in later chips, so hopefully this will go
away when you receive the new chip.

This is also something that others should be aware of if they have purchased
a used mount from another individual. It would be a good idea to check the
chip set that is in the servo (easily done by removing the cover plate), as well
as checking the keypad software version. Updating everything is not expensive
and can avoid headaches like the ones in this post.

Roland Christen

In a message dated 8/14/2007 12:14:14 AM Central Daylight Time,
cluster@... writes:

Hi Howard,

I upgraded to the version 4.12 but before doing that moved Pulse
guide on the top serial port and the Sky on the bottom. I connected
Pulse Guide and then the sky. Issue still occurred. I was thinking
how the previous owner had no issue BUT, he was using only one
cable. So I disconnected the 2nd cable and used only one. I can
only connect TheSky or Pulse Guide one at a time, however, the
problem went away including with the key pad. So I shut everything
off and tried again with 2 cables and problem was back. So I swicth
cables using one cable only and issue was gone. So this only happens
when I have 2 cables connected.

A storm moved in so I need to let it pass. Now it is time to remove
the connector and put each cable on its own USB/Serial (the one I had
before was 2 ports on one USB.) Still puzzled why this affects the
key pad but it does. I can't break it with one cable, although a
full nights use is the main test. I did use the 2 port serial
programming the key pad and had no issue, so my guess is the mount
does not like 2 serial ports that move the mount.

Does anyone else have Pulse guide and TheSky setup on 2 serial cables
and can slew everywhere with pulse guide or the keypad.

Again, the issue is when you hold the button down on either pulse
guide or the keypad for at least 20 seconds and let go, it usually
keeps slewing.

It is possible that the com port is not setting the state to off when
the button is release, I know the things are pickly. At this point
my work around is to use one cable. but I will still switch cables
and USB/serial to see if one of those are an issue.

Howard and the AP staff offer fantastic support. I did order the E1
chip as well

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