Club Light Controller
By: Alex Cerruti and Chris Wherry
EE476 -- Spring 2002
1. Add User Controls
If we had more time, we would have like to add more
user control functionality. For
instance, the user would be able to select which colors (out of the 9
colors) they want to use as well as program the sequence they will flash
in. We were thinking that we
could interface the keypad with the MCU so the user could set these
features as desired. Better
yet, we could add DMX controls!
DMX is a lighting industry standard way of
controlling lighting equipment. It allows for one controller to control
many lights. DMX is used for controlling mainly the brightness of
lights, and can be used for controlling moving lights, smoke machines,
strobe lights and so on. It basically consists of one 8-bit (on or off)
signal for each light which sets the brightness level of the light to
one of 256 levels.
Electrically, DMX is a bus where there is one transmitter and multiple receivers. DMX wiring uses 5-pin XLR connectors with 120 ohm shielded twisted pair wiring. The protocol used in DMX-512 bus is similar to normal serial communications (like RS-232 with 8 data bits + 1 stop bit) and operates at 250 kbps (arguably difficult using a microprocessor, but it can be done!).
2. Improve Color Wheel Speed
It would be nice if the stepper motor allowed us to change the colors
more quickly. We tried
increasing the voltage to the motor, but this does not appear to make
the motor spin more quickly. Additionally,
reducing the delay after each pulse is applied only causes the motor to
vibrate in position for values less than 5 milliseconds.
Perhaps one could make the stepper motor rotate faster by
starting the rotation using all four of the control lines, then once
momentum was established, one could reduce the rotation time by using
only every other control line.