Software Bisque Knowledge Base Article – 281

AUTOSTAR IGNORES TENTHS OF AN ARC MINUTE IN RA

ISSUE

When communicating with the Autostar version 1.3 via its built-in serial port, the Autostar ignores tenths of minutes for the set object right ascension “:Sr HH:MM.T#” command.

To duplicate this behavior, run HyperTerminal (9600, 8, None, 1, No Flow Control) and send the “:Sr HH:MM.T#” command immediately followed by the get object right ascension command “:Gr#” to retrieve the value just set. The retrieved value will not match the set value if right ascension’s tenth of a minute is non zero.

Here is sample HyperTerminal output:

:Sr 20:12.2#1
:Gr#20:12.0#

The set object right ascension command is how the Autostar is instructed to slew and sync on an object. The coordinates of the Autostar will not match the coordinates that were sent to it if tenths of a minute right ascension are required.

RESOLUTION

This is a limitation with the Autostar version 1.3 and can result in fifteen arcminutes of inaccuracy when this device is controlled via the serial port.

None.

More Information

Contact the telescope’s manufacturer to determine if an
updated version of the firmware is available.

APPLIES TO

Telescope Interface

KEYWORDS

SBKB

This article was formerly published under the identifier Q544KB in Software Bisque’s prior knowledge base.

Last Reviewed: 11/24/2004