BakeBit - JoyStick

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1 Introduction

JoyStick

• The BakeBit - JoyStick is a joystick module. It consists of two Sliding rheostats. Its positional states can be measured as X and Y axis values as the calibrated resistance of the two potentiometers.

2 Hardware Spec

• Standard 2.0mm pitch 4-Pin BakeBit Interface
• Analog Output
• PCB dimension(mm): 24 * 42

• Pin Description:

Pin	Description
GND	Ground
5V	5V Supply Voltage
X	X Axis Output
Y	Y Axis Output

3 Code Sample: UI Control via Joystick

By running this code sample you will see a simple configuration window and you can use the joystick to navigate and change a configuration item’s setting.
A BakeBit - OLED 128x64 module is needed in this test case.

3.1 Hardware Connection

Connect the joystick module to the NEO-Hub at A0 and the OLED module to the NEO-Hub at the I2C interface:

3.2 Source Code

import bakebit_128_64_oled as oled
import bakebit
import time
 
 
oled.init()                  #initialze SEEED OLED display
oled.clearDisplay()          #clear the screen and set start position to top left corner
oled.setNormalDisplay()      #Set display to normal mode (i.e non-inverse mode)
oled.setPageMode()           #Set addressing mode to Page Mode
 
# Uses two pins - one for the X axis and one for the Y axis
# This configuration means you are using port A0
xPin = 0
yPin = 1
bakebit.pinMode(xPin,"INPUT")
bakebit.pinMode(yPin,"INPUT")
 
texts = ["Wi-Fi"
    , "Bluetooth"
    , "Media Vol"
    , "Alarm Vol"
    , "FontSize"
    , "Brightness"
    , "Dim" ]
 
values = [True
    , False
    , 50
    , 50
    , 9
    , 80
    , 30 ]
 
opIndex = 0
m = int(1024.0/5)
while True:
    try:
        # Get X/Y coordinates
        x = bakebit.analogRead(xPin)
        y = bakebit.analogRead(yPin)
 
        oled.setTextXY(0,0)
        oled.putString("[Settings]")
 
        if x<m:
            # left
            print("left")
            if type(values[opIndex]) is int:
                values[opIndex]=values[opIndex]-1
                if values[opIndex]<0:
                    values[opIndex] = 0
            elif type(values[opIndex]) is bool:
                values[opIndex] = not values[opIndex]
 
        elif x>(1024-m):
            # right
            print("right")
            if type(values[opIndex]) is int:
                values[opIndex]=values[opIndex]+1
                if values[opIndex]>999:
                    values[opIndex] = 999
            elif type(values[opIndex]) is bool:
                values[opIndex] = not values[opIndex]
        elif y<m:
			opIndex = opIndex - 1
        elif y>(1024-m):
			opIndex = opIndex + 1
        elif opIndex<0:
			opIndex=6
        elif opIndex>6:
			opIndex=0
 
        for i in range(7):
            oled.setTextXY(0,i+1)
            valueStr = ""
            if type(values[i]) is int:
                valueStr = str(values[i])
            elif type(values[i]) is bool:
                if values[i]:
                    valueStr = "On"
                else:
                    valueStr = "Off"
            for j in range(3-len(valueStr)):
                valueStr = " " + valueStr
 
            title = texts[i]
            if len(title) > 10:
                title = title[:10]
 
            for j in range(10-len(title)):
                title = title + " "
 
            if opIndex == i:
                oled.putString("> " + title + " " + valueStr)
            else:
                oled.putString("  " + title + " " + valueStr)
    	print("x =", x, " y =", y, " opIndex=", opIndex)	
 
    except IOError:
        print ("Error")

Github

3.3 Run Code Sample

Before you run the code sample you need to follow the steps in bakebit tutorial to install the BakeBit package.
Enter the "BakeBit/Software/Python" directory and run the "bakebit_prj_UIControl_via_Joystick.py" program:

cd ~/BakeBit/Software/Python
sudo python bakebit_prj_UIControl_via_Joystick.py

3.4 Observation

When the program runs a simple configuration window will be presented on the OLED. When you move the joystick up or down the cursor will move up or down to a configuration item. When you move the joystick left or right the item’s setting will be changed accordingly.

4 相关资料

• [Schematic](BakeBit - JoyStick.pdf)
• [BakeBit Github项目](https://github.com/friendlyarm/BakeBit)
• [BakeBit Starter Kit手册](http://wiki.friendlyarm.com/bakebit/bakebit_starter_kit_manual_cn.pdf)