AUTOSTAR INFORMATION Last updated: 17 December 2000

Patch for "Creep after Beep"

From:	rseymour@wolfenet.com (richard seymour)
Care to try and lower creep-after-beep?

I believe the following patch will address a lot of it.
I noticed this quirk in the firmware back in v1.3c, but
following where it went and what it signified took this long.

Basically, in three locations, the firmware calls backlash
compensation twice (hence double-compensates) when once is enough.

The patch skips one of those calls at each spot.

Autostar 497 Firmware  (all numbers HEXadecimal)

Version     Locations
v2.0g    8BCAD   8F921  9A2F5

v2.0h    8BCAD   8F7B9  9A305

v2.0i  same as v2.0h

For all versions, at all three locations,
 change   BD 1F   to  20 04

(for further verification that you're patching the correct location,
the original bytes are 
 v2.0g: BD 1F 54 09 80 00    jsr 1f54 098000 
 v2.0h: BD 1F 0C 09 80 00    jsr 1f0c 098000
 v2.0i: BD 1F 0A 09 80 00    jsr 1f0a 098000
In each case, you're changing the "jsr 1f54" to "bra +04"
So instead of Jumping to the SubRoutine 1f54,
 you're now BRanching Always over that call.

As noted in previous patches, I use FRHED,
a freeware hex editor from http://www.tu-darmstadt.de/~rkibria

You just 
(a) make a BACKUP COPY of autostar.rom (found in the Ephemerides
directory)
(b) start frhed and use its File>Open dialog to open the Ephemerides'
autostar.rom  file
(c) use control-G to get the "goto" window
(d) enter  x8BCAD  into that, click [ok]
(e) the cursor will be on the byte that wants to be changed.
(f) type   2004  to change the "BD 1F" to "20 04"
(g) repeat steps c-d-e-f for x8F7B9  and x9A305
(h) use frhed's  File>Save to save the changes
(i) exit frhed
(j) fire up the Autostar Updater and click the [new software] button.

Note: the autostar.rom file is in the 
  ProgramFiles>Meade>Autostar>AutostarUpdate>Ephemerides
 folder.... NOT in the AutostarUpdate folder itself.
The above a-j shows the locations for v2.0h and v2.0i.

I'll try to come up with the 495's patch soon.
good luck
--dick

Volunteer sought: someone to write a small DOS executable that
will do such patches from a script list.
Input:  Location  Old  New

I find that the author's webhost is currently offline.

You can also pick up frhed at ZDNet's download site.

Here's the direct link to Frhed's page on ZDNet:

http://hotfiles.zdnet.com/cgi-bin/texis/swlib/hotfiles/info.html?fcode=000VOX&b=

good luck
--dick

Subject:	 creep-after-beep patch for 495 Autostar
Sent:	Tuesday, November 21, 2000 20:56:51
From:	rseymour@wolfenet.com (richard seymour)
(it turns out i don't have a copy of v2.0h for the 495.
The one on Mike's site seems to really be the 497's.
If anyone would zip and send me the v2.0h autostar.rom for the 495,
i'll provide the creep-after-beep killer for it, too).

Warning: this is untested (on a 495) since i don't own one.

The 495's software differs from the 497's in that it has a "checksum",
and the Updater will refuse to download it if the sum of all the bytes
in the firmware don't match a magic number.

Hence the 495's patch is slightly more complicated, since you have to
correct the final sum by adjusting a few more bytes.

To remove a double invocation of backlash correction after a [GoTo]:

The v2.0g and v2.0i patch for the 495 Autostar is/are:

Version v2.0g  Locations: 8BCC1, 8F935, 9A041
   Old:  BD 1F 54 09   
   New:  20 04 F1 24

Version 2.0i  Locations:  8BCC1, 8F7C,  9A051
   Old:  BD  1F  0A  09
   New:  20  04  A7  24          

So, that's in three locations in the firmware,
and you're changing four bytes at each location.
The first two bytes are the fix, the last two are the checksum fudge.

Refer to "creep-after-beep Squash it!" for how-to-patch instructions.

This zip file includes all files referenced by the web page,
although the webpage has hard ftp links to my web area.
good luck
--dick (not near his Email 24th Nov->26th Nov)

I recently posted the details of patching the Autostar firmware
to help kill creep-after-beep.  I included a plea for someone to
write a small DOS program to perform the patch, rather than requiring
everyone get deep into Hex dumping.

Jim Berry (of Astro QuickCam fame) provided such a wee beastie.

You can access it from 
http://www.wolfe.net/~workshop/astro/patcher.html

That has links to patch scripts for 5 flavors of autostar.rom,
the patch program itself, and a batch file to make it (almost)
drag-and-drop simple.

enjoy
--dick

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