Page 203 - Build Your Own Quadcopter_ Power Up Your Designs with the Parallax Elev-8

182 Bu il d Y o ur O w n Q u a d c o p t e r

Figure 7.21 Transistor driver circuit.

the special characters used to create the schematic do not copy over using the Word program’s
copy and paste functions. Figure 7.21 shows a screenshot of the schematic portion.

{{
LED_Control
D.J. Norris (C) 2013
This program sets the LED lighting mode for the four LED strips
attached to the underside of the Elev-8 booms. The mode is selected
based upon the Flap switch position on the Spektrum DX-8 R/C
transmitter.
The three possible positions with associated modes and pulse widths
are:

Position Mode Pulse Width
0 Flash front boom LEDs only 1.899 ms
1 Flash all LEDs 1.505 ms
2 No LEDs are lit or flashed 1.111 ms

Driver schematic

See Figure 7.21, since as already mentioned, Word copy/paste does
not work with the special characters used to create the Spin
documentation schematic.

}}

CON
RIGHT_FRONT = 1
LEFT_FRONT = 2
RIGHT_REAR = 3
LEFT_REAR = 4
WAIT_CNT = 40_000_000
RIGHT_FRONT_PIN = 5
LEFT_FRONT_PIN = 6
RIGHT_REAR_PIN = 7
LEFT_REAR_PIN = 8

VAR

long stack[20]