[Barrykgerdes]

Hi Andrew
I wrote those programs in the days when computer processors worked in Hz rather than GHz. So the loop only polled the telescope once every few seconds and each request had to wait for an answer. In the mean time the program looks for key presses, calculates the time, sidereal time etc every loop.

With the speed of the modern processors the loop runs much faster but as you say lots of the answers to requests are read more than once within the cycle of their calculation in the controller. Practically this is not noticed.

Actually there are two versions of the LX200 and ETX controllers. One is just a mirror of what is in the telescope. The other only uses the positions read from the position in the controller, resets the buffer and sends a goto command as required and all the sky data is read from an appropriate data base. This format allows me to use the main source to control Celestron and Synscan as well as the Gemini by just changing the commands that read and write to the scope

Barry

PS I don't normally use these programs in the field. I just use them to run my LX200 test set, Heq5 and Gemini mounts to test that the computer can talk to the telescope.

BG