SMARS - the Screwless Modular Assembleable Robotic System.
To download the files visit https://www.thingiverse.com/thing:2755973
5
Connect the Raspberry pi Zero using the following pins:
PCA9685 GND to RPI Pin 39 (or Pin 6) - Black wire
PCA9685 V+ to RPI Pin 2 - Red wire
PCA9685 SCL to RPI Pin 5 (SCL) - Green wire
PCA9685 SDA to RPI Pin 3 (SDA) - Blue wire
Note that the input voltage for the PCA9685 is 3.3v or 5v into the VCC. The V+ is for powering the
servo motors and requires more power than the raspberry pi can provide, which is why it is separate.
You can use a 9v battery to drive this, using the SMARS 9v case.
The raspberry pi communicates with the servo driver board using I2C, which only requires 2 wires:
System Clock (SCL) and System Data (SDA). These are marked on servo driver board, and on pins 3 & 7
on the Raspberry Pi Zero.
0
1
GND
V+
POWER
16x12-bit PWM
PCA9685
PWM
V+
GND
2 3
GND
OE
SCL
SDA
VCC
V+
I2C Address
(Open=0/Closed=1)
GND
OE
SCL
SDA
VCC
V+
4
5 6 7
8
9 10 11
12 13 14 15
A5 A4 A3 A2 A1 A0+RW
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
40
5v Power
5v Power
Ground
BCM 14 (TXD)
BCM 15 (RXD)
BCM 18 (PWM0)
Ground
BCM 23
BCM 24
Ground
BCM 25
BCM 8 (CE0)
BCM 7 (CD1)
BCM 1 (ID_SC)
Ground
BCM 12 (PWM0)
Ground
BCM 16
BCM 20 (MOSI)
BCM 21 (SCLK)
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
35
37
39
3v3 Power
BCM 2 (SDA)
BCM 3 (SCL)
BCM 4 (GPCLK0)
Ground
BCM 17
BCM 27
BCM 22
3v3 Power
BCM 10 (MOSI)
BCM 9 (MISO)
BCM 11 (SCLK)
Ground
BCM 0 (ID_SD)
BCM 5
BCM 6
BCM 13 (PWM1)
BCM 19 (MISO)
BCM 26
Ground
QUAD ROBOT
PI ZERO SETUP
S
M
A S
R
