© Gooligum Electronics 2015
www.gooligum.com.au
Baseline and mid-range PIC training and dev board operation guide
Page 7
A sawtooth form of the variable frequency signal can be connected to comparator input
C2IN+
, via
jumper JP27.
A piezo sounder is connected directly to pin
RC5
, which is also PWM output
P1A
.
To drive the piezo using a single-ended PWM output (or by toggling
RC5
), the other side of the piezo
should be connected to ground, by placing a shunt across positions 1 and 2 of jumper JP23.
Alternatively, the piezo can be driven (at higher volume) by a double-ended or half-bridge PWM output,
by placing a shunt across positions 2 and 3 of JP23, connecting its other side to PWM output
P1B
.
Finally, every PIC pin, the 32.768 kHz and variable frequency signals and the power supply are brought
out to a 16-pin
expansion
header, next to the
breadboard
(making it easy to build custom circuits and to
use this training board a general 6 – 14-pin PIC development board), as follows:
Pin
Description
1
32.768 kHz buffered digital signal
2
GP5 / RA5 / RB5
3
GP4 / RA4 / RB4
4
GP3 / RA3 / RB3
5
RC5
6
RC4
7
RC3
8
GP0 / RA0 / RB0
9
GP1 / RA1 / RB1
10
RC0
11
RC2
12
RC1
13
GP2 / RA2 / RB2
14
Variable frequency (150 – 10000 Hz) digital signal
15
Power (+V)
16
Ground
