Updating meade autostar 497 controller

(The Autostar II is used in the LX200GPS, LX200R, RCX400 and Max Mount.

In all of those mounts, the "brains" are in the telescope base and the handbox is merely a "dumb" peripheral which is not actually required for telescope operation) Photographs of the insides of the 494 and both 497 models are here, along with sketches of the components.

At that point the previous 497 firmware would tell you "File Space Full... What it's doing is copying the -active- objects in the 63Kbytes to those upper "spare" pages. Then it copies the 63Kbytes (now cleaned of the deleted objects) back to the usual space.

Newer 497 firmwares and the 494/Starfinder either get confused or tell you "File Space Full", since they no longer have that extra space.

One side has all of the active components on it (the "chips"). It has only the soldered contact pads for the conductive dots on the keypad.

Those solder pads can oxidize over time, and cleaning them can help restore poor keypad sensitivity.

The "new" 14-pin display module is the same one used in the 494, and in the Autostar II's handbox.

The Flash Ram can be rewritten by the Autostar itself.

It's the same type of memory that is used by digital cameras.

The other, chip-covered, side is where all the fun happens.

Here are rough pictures of the components you'd see with the backs off: The computer portion of the Autostar is the Motorola 68HC11.

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