描述

一、PCA9685簡介

The PCA9685 is an I2C-bus controlled 16-channel LED controller optimized for LCD Red/Green/Blue/Amber (RGBA) color backlighting applications. Each LED output has its own 12-bit resolution (4096 steps) fixed frequency individual PWM controller that operates at a programmable frequency from a typical of 40 Hz to 1000 Hz with a duty cycle that is adjustable from 0 % to 100 % to allow the LED to be set to a specific brightness value. All outputs are set to the same PWM frequency.

PCA9685 also has a built-in oscillator for the PWM control.However, the frequency used for PWM control in the PCA9685 is adjustable from about 40 Hz to 1000 Hz as compared to the typical 97.6 kHz frequency of the
PCA9635. This allows the use of PCA9685 with external power supply controllers. All bits are set at the same frequency.

The PCA9685 has 4096 steps (12-bit PWM)

二、產品特色

1. J3 Mini USB 5V input for PWM V+ & GPIO output pin 10 V+

J2 2P Terminal Block 5V input for PWM V+ & GPIO output pin 10 V+

2. J1 Rs-Pi V2  GPIO output

3 JP13  DA0 ~ DA7   U14 Port A    . JP14 BA0 ~ BA7     U14 Port B

4. R64,R65,R66 ( for  U14 Address select  A0,A1,A2)

5. U14 SPI 23s17 -1  Port A,B            23s17 Datasheet

6. U15  uln2803

7. U3 PCA9685 (PWM Port 0 ~ 15)       PCA9685 Data Sheet 

8. R10,R11,R12,R13,R14,R15( for U3 Address select A0,A1,A2,A3,A4,A5)

plug in Raspberry Pi with Servo motor

in i2cdetect  you can found 1 device in system (41)

41 – 9685

our new output test program    23s17-1port-v100.py   display all 16 GPIO status

三、Scratch驅動應用範例 Detail

(1) 23s17 16 GPIO control

U1 to U4 spi 23s17  address 40,42,44,46

U1 to U2 spi 23s17  address 40,42

 

40 –> 1  42 –> 2  44 –> 3  46  –> 4

48 –> 5  4a –> 6  4c –> 7  4e  –> 8

 

Command “sp“+ “address(1-8)” + “a” +”bit(1 to 8)” for Port A

Command “sp“+ “address(1-8)” + “b” +”bit(1 to 8)” for Port B

Command “bits“+ “address(1-8)” + “a” +”bit(8 to 1)” for Port A

Command “bits“+ “address(1-8)” + “b” +”bit(8 to 1)” for Port B

sp2b7 –>  spi address 2 Port B bit 7 ON/OFF

sp3b4 –>  spi address 3 Port B bit 4 ON/OFF

bits2b01010101 –>  address 2 port B from bit 8 to 11

output  –> 01010101

bits2a01010101 –>  address 2 port A from bit 8 to 1

output–>01010101

bits2aoff  –> address 2 Port A all OFF/clear

bits2aclr  –> address 2 Port A all OFF/clear

(2) Servo Motor control

2 Servo in  channel 0 & channel 7

Command “SE”+ “PWM (0-15)” + “a” +”angle”  for Address 41

se7a10   –> channel 7 servo move 10 angle  address 41

se7a-10  –> channel 7 servo move -10 angle address 41

se0a10   –> channel 0 servo move 10 angle  address 41

se0a-10  –> channel 0 servo move -10 angle  address 41

(3) PWM  LED output demo

LED module (Blue, Green,Yellow,Red)

 

LED Scrolling  Command     PWMLED41S0E15D4True

PWMLED”Address” S[Start channel] E[End channel] D[Delay / Timing] [True/False]

 

Address 41, 42,43,44

Start channel & End channel   0 ~ 15    16 channel

D   1,2,3,4,5    (1 ~ 100) Delay Timing

 

LED Brightness control Command

PWMLED “Address” “B” “0 ~ 1000“

PWMLED41B1000

 

Stop command

“PWMLED41STOP”

四、範例程式下載

23s17-1port-v100.py

n23s17-cs0.py

23s17-cs0.py

servo-40.py

servo-41.py

pwm

五、產品內容

1x Rs-Pi I2C 16 channel PWM &  SPI 23s17-1  16 GPIO board

1x User manual