The 40 inch filter wheel is 6 slotted filter wheel, controlled over the network through NG protocal. It uses a stepper motor for motion and a hall effect sensor and encoder for homing and positioning respectively. It is controlled by an Arduino Ethernet and a LIN Engineering stepper driver.
The wheel uses NG Protocol developed by Steward Observatory. Its observatory ID is CSS40 and its SYSid is FW40. Each command or request requires a trailing newline.
NAME | # of ARGS | DESCRIPTION |
---|---|---|
FNUM | 0 | Returns the current filter wheel number |
MOT | 0 | Returns the motion status |
Name | # of Args | Description |
---|---|---|
GOTO | 1 (fnumber) | Sends the filter wheel to the given number |
DISABLE | 0 | Disables the stepper motor |
ENABLE | 0 | Enables the stepper motor |
SETHOME | 1 (Home Pos) | Sets the home position in offset counts first detecting the home sensor. |
SAVEHOME | 1 (Home Pos) | Saves the given home position to the eeprom so it will use this value on start up. This will permanently change the home position!!! Use at your own peril!!! |
HOME | 0 | Moves to the home positon. |
STOP | 0 | Stops all motion |
You can find the arduino source code and an example python program for the network communication here .