this is valid for both v2.0h and v2.0i for a #497 (ETX) Autostar. This patch changes the "valid range" of Eccentricities for Comets from its current: zero to (Not quite) 1.0 to: zero to 1.5 Thus allowing Meade's TLE data for comet Linear S4 to be entered and tracked. Three locations must be changed: loc old new 3F851 80 C0 3F8A4 80 C0 59190 80 C0 That changes a "ldd #x3F80" to "ldd #x3FC0" 3F80 is binary floating point for 1.0000 3FC0 is binary floating point for 1.5000 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 (c) use control-G to get the "goto" window (d) enter x3F851 into that, click [ok] (e) the cursor will be on the byte that wants to be changed. (f) type a "C" to change the "8" to "C" (g) repeat steps d-e-f for x3f8a4 and x59190 (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. have fun --dick
From: email@example.com (richard seymour) I am pleased to report that the patch i sent about the 497 autostar also works for the 495 Autostar, version 2.0i (and probably 2.0h). But: there is one additional operation when patching the 495 Autostar. Meade uses a "checksum" during the uploading, so a value has to be added to the file to correct for the change. In the satellite-to-the-second patch (STTS, see below), the new values were smaller than the originals, so we only had to add the difference. In this patch, the new values are larger, so the extra byte becomes a puzzle. *I* do not have a 495. So i cannot test various values. If they do a signed byte-sum, then the extra value will probably be 40 (hexadecimal). Also, the STTS patch bytes were all on even locations, so they lined up during a 16-bit summation. The Eccentric patch falls on both even and odd bytes. That may also affect the checksum. Only testing (or Meade telling us what to do) will yield an answer. (the test is benign... the Autostar Updater complains about the file, rather than downloading it). So: to allow your Autostar to accept (from the keypad) and track Comets with eccentricities greater than or equal to one, change the following four locations: (the first three match the 497)(all numbers are Hex) Location old new 3f851 80 c0 3f8a4 80 c0 59190 80 c0 a0000 (empty) 40 (?) An alternate approach would be to subtract the extra value from an unneeded byte. In that case, i'd suggest changing 9ffd0 from ff to 3f Good luck... if you try this, please let me know which fourth-byte method worked! --dick firstname.lastname@example.org p.s. STTS: in case you missed it, you can get the Autostar to report Satellite AOS times to the second. Since pushing [select] multiple times for the same pass of the same satellite can get different results, this helps choose the best AOS for your situation. (all numbers are Hex, works for 2.0g/h/i) For a 495: Loc old new 59510 84 6f 59524 84 6f a0000 (empty) 2a For a 497: Loc old new 594fc 4c 37 59510 4c 37 p.p.s. If you want to do -both- patches on a 495, make one of the "extra" bytes be at A0001, or sum them (hence 2a+40=6a)
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