Starlight Xpress SX Universal filter wheel - Manual (Page 4)

Handbook for the SX Universal Filter Wheel - Issue 1, May 2009
- 4 -
Manual Control:
A manual control box is available from Starlight Xpress dealers. The kit includes an
RJ12 cable to connect to the serial port of the wheel with the other end plugged into
the manual control box. The box contains a ‘AAA’ size battery clip for 4 cells and a
10 position thumb-operated rotary switch (switch positions higher than the maximum
number of filters will default to the highest number available – i.e. switch positions 8
and 9 give filter 7 on a 7 aperture filter wheel). To install the batteries, unscrew the
four cross-head screws in the rear panel of the hand controller and lift it off. The
battery holder may then be lifted out and fitted with four AAA cells.
Please be sure to disconnect the hand controller when it is not in use, or the battery
pack will be discharged.
Starlight Xpress Universal Filter Wheel
Communication Protocols
Interfaces available:
(a) USB: 1.1 or 2.0
(b) Serial Port: 9600 baud, 8 data bits, no parity, 1 stop bit.
(c) Manual Switch: Select filter using digital switch box.
General parameters:
Total Filters: This is the number of filters fitted on the wheel, and is currently
5 or 7.
Filter number: This is any number from 1 to
(If a Filter Number higher than Total Filters is requested then the Filter
Number is set to )
USB Protocol:
The SX filter wheel uses a simple “Human Interface Device” protocol, so no
special driver needs to be installed. The driver is an integral part of the
Windows PC operating system.
Communications between the PC & filter wheel is by input and output reports
(referenced to the PC). These reports are both of a fixed length of two bytes.
The PC sends the output report and the filter wheel, about 1ms later, will send
an input report in response.
The output report data is formatted thus:
Description 1
st
byte 2
nd
byte
Select Filter New Filter number Zero (0)
Request current filter number Zero Zero
Get Filter Total Zero One (1)
The input report data is formatted thus:
Response To: 1
st
byte 2
nd
byte
Select New Filter New Filter number
or
Zero = filters moving Total filters
Request current filter number Current Filter number Total filters