Last updated: 23 May 2004

Patch kit for LX200gps v2.0i

Subject:	updated patchkit  for LX200gps v2.0i
Sent:	Wednesday, May 19, 2004 23:14:20
From:	Richard Seymour (
While working with Andrew Johansen (trying to figure out if PEC
is still broken in the Southern Hemisphere in v2.0i) i discovered
that my PEC-readout patch was incorrect for the Training phase
(it works properly in Update mode).  
So i fixed it, and here is the NEW patch kit for v2.0i,
which i've labelledd

This kit will display (properly) the PEC values as you Train
or Update the scope, it will display (and allow you to Edit)
your Drive Training values.  It will allow you to start tracking
a satellite when the count-down reaches zero.  It fixes the
LX200 serial command :MA# so that the scope really will
remotely GoTo an Alt/Az target.  
It also adds a :gpr# serial command which will return 
the next GPS receiver "sentence", regardless of type.
The kit includes a text file describing how to decode/
interpret the GPS receiver data.

have fun

Subject: corrrected LX200gps v2.0i patch kit
Date: 3/13/04, 11:43
From: Richard Seymour (
There was an error in my Jan 6th LX200gps patch kit,
which affected the automatic start of satellite tracking.
(when the timer reached zero, it would abort the track).

The attached kit is a complete replacement for the previous kit.

my apologies for not catching this earlier
(just goes to show how many clear nights i've had)

have fun

Date: 1/6/04, 19:21
From: Richard Seymour (
6-Jan-2004 v2.0i->v2p0I  Dick Seymour's Patch Kit for LX200gps
What this kit gives you:

  ** Displays PEC values during Update/Training **
  Display and Editing of Drive Training Values
  Automatic Satellite Track starting at down-count=zero  (optional, see below)
  Guiderate range expansion to +25,700% (from 100%).
  Version number change from 2.0i  to 2p0I (lowercase p, uppercase I )
  adds :gpr# serial command to return all GPS receiver sentences

How to use the features:

During a PEC Training or Update session, will display the previous
segment's correction value beside the index number.
If you wish to just -view- the numbers, start a PEC Update run,
and simply do not touch the slew keys.
Due to the way Meade does the Train/Update, the index number may change
from run to run, but the sequence order of the data will be the same.
If you choose to include the automatic satellite tracking patch, then the scope
will start to track a satellite when the timing count-down hits zero.
Unlike the "normal" firmware, the beep will NOT sound when tracking starts.
The Settings > Telescope > Guide Rate [enter]  will now accept up to 25700%
Under Settings > Telescope > Drive Train  are added two more submenus:
  Edit > Az Train   and  Edit > Alt Train
If you press [enter], the Autostar will display the results of your last
  Drive Training session.  The numbers also allow -input-, so you can investigate
  the effects of more or less aggressive training results.  
If the numbers get totally out-of-whack, remember that a "for real" Training
  session will re-establish them, as will a Setup > RESET [enter]
The factory default settings are +30 for both axes.

"Az Train" is the same as "RA Train", "Alt Train" is the same as "Dec Train"

--- Enhanced GPS readback:
If you send the rs232 port a :g+#  command, it turns on the GPS receiver.
Then if you send it :gpr#  commands, it will return whatever string the
  GPS receiver is willing to provide.  I have seen:
*   $GPGGA - Global Positioning System Fix Data
*   $GPGLL - Geographic position, latitude / longitude
*   $GPGSA - GPS DOP and active satellites
*   $GPGSV - GPS Satellites in view
*   $GPRMC - Recommended minimum specific GPS Coordinates (above)
*   $GPVTG - Track made good and ground speed
*   $GPZDA - Date & Time

The kit includes a "GPSdecode.txt" file describes how to interpret the
GPS receiver strings.

have fun

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