Alphabot2 for micro:bit User Manual Alphabot2 for micro:bit User Manual 1 / 76
Alphabot2 for micro:bit User Manual CONTENT Preface .......................................................................................................................................................... 5 micro:bit ............................................................................................................................................... 5 Notes ............................................................................................................................................
Alphabot2 for micro:bit User Manual Play Piano .......................................................................................................................................... 27 Play melody 2 ................................................................................................................................... 28 Chapter 5 RGB LED ................................................................................................................................. 29 Add package...........
Alphabot2 for micro:bit User Manual Bluetooth Connecting 2 ............................................................................................................... 51 D-Pad controller .............................................................................................................................. 53 D-PAD Controller 2 ........................................................................................................................ 55 Chapter 9 2.4g Radio ..........................
Alphabot2 for micro:bit User Manual PREFACE This Alphabot2 robot kit uses the BBC micro: bit as the host controller, combined with several functional modules, it is easy for the kids to experience robotic tricks such as line tracking, obstacle avoiding, ultrasonic ranging, servo operation, Bluetooth remote control, etc. MICRO:BIT The BBC micro: bit is a pocket-sized computer to learn programming for kids and beginners ⚫ Nordic nRF51822 ◼ 16 MHz 32-bit ARM Cortex-M0 microcontroller ◼ Bluetooth® 4.
Alphabot2 for micro:bit User Manual ⚫ 5x5 LED display – 5x5 LED grid ⚫ Button A/B – programmable buttons ⚫ I/O connection pins – 5 I/O rings and 20-pin edge connector, including SPI, UART, I2C, Analog, PWM, etc. Dimensions – 5cm x 4cm ⚫ NOTES 1. Components in different package will be different. In this guide, we describe all components, and some of them may not be included in the package you buy. 2.
Alphabot2 for micro:bit User Manual 6. You must turn on the power switch and make sure the battery supplies power normally before you connect USB cable to micro:bit for programming. You cannot power Alphabot2 by micro:bit, otherwise the power LED's light is very slight and Alphabot2 will work improperly. 7. You must turn off power before you plug/pull micro：bit, to avoid of destroying micro:bit. And please keep the LED matrix of micro:bit towards to outside. 8.
Alphabot2 for micro:bit User Manual CHAPTER 1 LED LIGHTS The micro:bit has 25 (5x5) individually-programmable LEDs, allowing you to display text, numbers and images, here we will learn about coding these LEDs. JAVASCRIPT BLOCKS E DITOR The link of online JavaScript Block Editor of BBC: https://makecode.microbit.org/# Accessing the editor.
Alphabot2 for micro:bit User Manual BLOCKS Blocks in Basic are mainly used for basic operation like LEDs controlling.
Alphabot2 for micro:bit User Manual : Draw an image on the LED screen (LEDs) : Scroll a number on the LEDs : Display text on the LEDs, display one character at a time. : Draw selected icon on the LEDs : Turn off all LEDs : Draw an arrow on the LEDs LIGHTING LEDS Connecting the micro:bit to computer via a micro USB cable, the micro:bit will show up on your computer as a drive called “MICROBIT”. Now let’s start our first code that to light the LEDs with the blocks we describe above.
Alphabot2 for micro:bit User Manual Click the LED to make them light on, you can see that the LEDs of simulated micro:bit light on as the codes. Click Download to download the code to the drive of micro:bit. You can also save the HEX file to another place, and then copy to micro:bit instead of directly download to micro:bit.
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Alphabot2 for micro:bit User Manual HEART BEATING This code, we use block show icon, first display big heart icon then the small heart. Repeat the code and it looks like heart beating. Let’s do it.
Alphabot2 for micro:bit User Manual DISPLAY TEXT Here we use show string block to display text “Hello!” on LEDs. The text will scroll on LEDs character by character. 【Tips】 To delete the blocks, you can right click and delete it or just drag it to the left side.
Alphabot2 for micro:bit User Manual CHAPTER 2 BUTTONS There are two programmable buttons on the front of the micro:bit, which are labelled A and B. In this chapter, we will code with these buttons. PRESSING Blocks we use in this section are included in Input package. With this block, if A or B buttons on your micro:bit are pressed, codes are executed. Coding the buttons to display characters, A when button A is pressed, B when button B is pressed, and C when both buttons are pressed. 1.
Alphabot2 for micro:bit User Manual 2. Place show string block in on button pressed block to display string on LEDs display. Duplicate and complete the script to as below: 3. Connect your micro:bit to PC, click Download to flash the code to your board. Press buttons on micro:bit to test if expected string is displayed. PRESSING 2 There is another way to detect buttons. In last section, codes are run when button is pressed, here we use if then and button is pressed blocks to do the same thing.
Alphabot2 for micro:bit User Manual if then block is in Logic package, button is pressed block is in Input package. 1. Place if then block on forever, then put button is pressed block on it. 2. Place show string block, then clock ⊕ icon to complete the codes as below: 3. Connect your micro:bit to PC, click Download to flash the code to your board. Press buttons on micro:bit to test if expected string is displayed. 【Tips】 Some users may notice that in this script, A+B are detected first instead of A or B.
Alphabot2 for micro:bit User Manual CHAPTER 3 SENSORS Micro:bit integrates Temperature sensor, Accelerometer, Compass and so on. In this chapter, we learn to use these sensors. TEMPERATURE SENSOR This sensor allows the micro:bit to detect the current ambient temperature in degree Celsius. It is embedded in the main chip nrf51822, which is used to detect the temperature of chip in fact. Even temperature of chip is a little different with ambient temperature, but we can use it to get an approximate value.
Alphabot2 for micro:bit User Manual 3. Add one pause (ms) for delay. 4. Download the code to your micro:bit, touch the CPU ( the main chip) for a moment, you will find the temperature became higher. ACCELEROMETER The accelerometer MMA8652 is integrated on the left bottom of micro:bit . Acceleration is a trend to move. If we apply a force to an object in one direction, then the object will trend to move in the direction, we call this trend the acceleration.
Alphabot2 for micro:bit User Manual feet, we will free-fall. It is that we have a trend to falling, which is called the acceleration of gravity written as g in formulas. We measure coordinate of x, y and z directions. With these three values, we could get the direction of accelerations. If there is only acceleration of gravity, the direction is downward. We keep measuring values of x, y and z coordinates to get the acceleration of micro:bit, and detect actions like shake, tilt and so on 1.
Alphabot2 for micro:bit User Manual 3. Duplicate and complete the script 4. Download the code to your micro:bit, shake your micro:bit to see if arrows change. MAGNETOMETER The compass chip is MAG3110, marked by red frame. The compass can detect the earth’s magnetic field by measuring x, y and z coordinates as well.
Alphabot2 for micro:bit User Manual Magnetic Force: We create a script to show the intensity of magnetic force by bar graph (LEDs) 1. Place plot bar graph of block to forever, which is in Led package 2. Place magnetic force (uT) block on the bar block, which can be found on Input->More, than set the max value to 255 3. Download the script to your micro:bit 4. When you first time run the code on micro:bit, it will scroll text “to fill screen” to tell you that calibration step should be done first.
Alphabot2 for micro:bit User Manual geomagnetism always points to north of geomagnetism. Combine with accelerometer and magnetometer, we can get the direction of North. 【Note】 we you use compass, you should keep your micro:bit be static and cannot be influenced by other magnetic fields. 1. Place show number block to forever 2. Find block magnetic heading (°) to number block 3. Add pause block for delay 4. Download the script to your micro:bit and try it. 5. Calibration also need to do after downloading.
Alphabot2 for micro:bit User Manual 2. Drag light level block to bar block, set max value to 255 3. Download the script to your micro:bit and try 4. Open the flashlight of your mobile phone and try to light the LEDs with it.
Alphabot2 for micro:bit User Manual CHAPTER 4 MUSIC Micro:bit doesn’t have buzzer or speaker, so if you want to make your micro:bit to play sound or music, you need to connect external speaker. There is a buzzer on Alphabot2-for-micro:bit expansion board, you can insert the micro:bit to it. 【Note】 Before you read this chapter, you’d better to assemble the Alphabot2 for mciro:bit.
Alphabot2 for micro:bit User Manual PLAY A MELODY Blocks for music can be found on Music package. 1. Place start melody repeat block to on start or forever 2. Choose one melody like birthday and set it to repeat once. 3. Download the script to your micro:bit and test if the melody is played. 【Tips】 sound is generated by shaking of object. People speak by shaking our vocal cord in different frequency.
Alphabot2 for micro:bit User Manual PLAY PIANO Let’s use blocks to simulate piano. 1. Place play tone for block to forever, set the tone to Middle C and 1 beat 2. Duplicate and complete the script as below 3. Download the script to your micro:bit, speaker connected will repeat tones “do”, “re”, “mi”, “fa”, “sol”, “la”, “si”.
Alphabot2 for micro:bit User Manual PLAY MELODY 2 We create a new project, to play different melody when buttons are pressed. 1. Place on button pressed block and set the start melody repeating on it 2. Duplicate and complete the script as below 3.
Alphabot2 for micro:bit User Manual CHAPTER 5 RGB LED Alphabot2 has four full color RGB LEDs, which are programmable for colorful effect. In this chapter, we code the RGB LED.
Alphabot2 for micro:bit User Manual ADD PACKAGE Before coding, we should add Neopixel package, click More… icon on top right, choose Add package (Extensions), then click neopixel.
Alphabot2 for micro:bit User Manual LIGHTING We create a new project, and code to light all the RGB LED 1. Place Set item to NeoPixel at pin P8 with 4 leds as (GRB format) block to on start -Variable item can be renamed -Pin P8 is selectable and P8 is the default pin of Alpahbot2’s RGB LED 2. Place item show color red -item should be same as the last block -color red is changeable 3.
Alphabot2 for micro:bit User Manual DISPLAY DIFFERENT COLORS We modify the last script to make four RGB LEDs to display different colors, for example, red, yellow, green and blue 1. Delete block item show color red by dragging it to the left side 2. Place item set pixel color at 0 to red block -This block can be found in Neopixel->More -This block can set the color of every pixel from 0 3. Duplicate and complete four LEDs 4.
Alphabot2 for micro:bit User Manual BLINKY LEDS We modify the last script to cycling RGB LED display. 1. Place item rotate pixels by 1 block in forever -This block can transfer the color of current pixel to next one 2. Place item show and pause (ms) blocks - item show block is necessary 3.
Alphabot2 for micro:bit User Manual RAINBOW We create a new project, coding four RGB LEDs for rainbow effect. 1. Place Set item to NeoPixel at pin P8 with 4 leds as (GRB format) block in on start 2. Create a variable hue, place set hue to 0 - these blocks can be created and founded in Variables package 3. Place change hue to 1 block in forever 4.
Alphabot2 for micro:bit User Manual CHAPTER 6 MOVING, ROBOT We have learned how to control LEDs and buzzer. In this chapter, let’s control the Alphabot2 and let it move.
Alphabot2 for micro:bit User Manual ADD PAKCAGE Adding a package like what we do in last chapter. Input the address on box: https://github.com/waveshare/pxt-AlphaBot2 , Click AlphaBot2.
Alphabot2 for micro:bit User Manual MOTORS We create a new project to control the motors of Alphabot2 by buttons. 1. Place If then and button is pressed blocks in forever 2. Place Motor speed block after then - This block is used to control one motor, the range of speed is -255 to 255, bigger the number, fast the speed. Positive to forward, and negative to backward. 3. Duplicate and complete the script 4. Download the script to micro:bit and test 5.
Alphabot2 for micro:bit User Manual MOVING We create a new project. Let Alphabot2 moves forward, backward, turns left and turns right by coding. 1.
Alphabot2 for micro:bit User Manual 3. Duplicate and complete the script as below 4.
Alphabot2 for micro:bit User Manual MOVING 2 There is another block can also be used to control motor. 1. Place Forward speed 0 block in on start - This block can directly control the robot to move in all directions 2. Place pause (ms) block 3. Duplicate and complete the script as below 4.
Alphabot2 for micro:bit User Manual MOVING 3 There is another block which can control robot to move for a certain time. 1. Place Forward speed 150 for 2 sec block in on start - With this block, robot will move forward in speed 100 for 2 seconds then stop if there is not another setting 2. Duplicate and complete the script 3. Download the script to micro:bit and test 4. After downloading, robot will move forward for 1 second, then backward for 1 second, and turn right, turn left, finally stop.
Alphabot2 for micro:bit User Manual CHAPTER 7 INFRARED OBSTACLE AVOIDING Two infrared sensors are integrated in the front of the Alphabot2-Base board, if you have assembled the Alphabot2, they are under the Ultrasonic sensor. Every infrared sensor has one sender and one receiver, infrared lights are sent from the sender, if there is obstacle in the front, some of them will be reflected and received by the receiver. There are green LEDs beside infrared sensors to indicate obstacles.
Alphabot2 for micro:bit User Manual INFARED SENSOR STATUS 1. Place if then block in forever 2. Replace true with and block 3. Put Infrared block to both sides of and 4. Place show string block 5. Duplicate and complete the scrip 6. Download the script to micro:bit and test it. 7. After downloading, LEDs of micro:bit will display “A” if obstacle is detected by both infrared sensors, “L” if obstacle is detected by the left infrared sensor and “R” if obstacle is detected by the right sensor.
Alphabot2 for micro:bit User Manual OBSTACLE AVOIDING We modify the last script to make robot to avoid obstacle. 1. Place show string block with speed block to make robot turn right when obstacle is detected. 2. Place pause (ms) block 3. Place Forward speed block after else to let robot move forward 4.
Alphabot2 for micro:bit User Manual CHAPTER 8 BLUETOOTH Nrf51822 is a BLE (Bluetooth Low Energy) module allows micro:bit to send and receive Bluetooth signals. With this feature, we can control robot by our mobile phones via Bluetooth. ADD PACKAGE To use Bluetooth, we need to first add the supports package. Note that the Bluetooth package is incompatible with extensions ws2812b, neopixel and radio.
Alphabot2 for micro:bit User Manual BLUETOOTH CONNETION Before programming, you need to install the Bluetooth APP to your phone. (This app only support Android) ⚫ Bluetooth App for Android 1. Place bluetooth *** service blocks in on start - This there are several services can be used 2. Place on Bluetooth connected and show string “C” blocks - Make micro:bit show “C” if Bluetooth is connected 3.
Alphabot2 for micro:bit User Manual 6. Open Bluetooth service of your phone, scanning and find the BBC micro:bit device, pair with it and connect. After paring, icon “√” is displayed. Note that you should delete paired micro:bit device before a new pairing. 7.
Alphabot2 for micro:bit User Manual 8. Click BBC micro:bit (BOUNDED) to connect. Note that only the device with (BOUNDED) suffix can be connected. 9. After connecting, control options are listed as below, and LEDs matrix shows “C” 10. Then you can try to control micro:bit by Bluetooth. Click Accelerometer, tilt your micro:bit, and the micro:bit image in APP tilt as well.
Alphabot2 for micro:bit User Manual 11. Click button option. Press buttons of your micro:bit. The buttons icon in APP react the button event. 12.
Alphabot2 for micro:bit User Manual 13. Click Temperature option, the current temperature is showed in APP 【Note】We only start four services in the code, so some of the services showed in APP are unavailable.
Alphabot2 for micro:bit User Manual BLUETOOTH CONNECTING 2 To connect with micro:bit, we should first pair then connect, there are two much steps. Here we modify the last script to make it simpler. 1. Click the icon on the top right: More… ->Project Setting, check the first option “No Pairing Required: Anyone can connect via Bluetooth” 2. Download the script to micro:bit 3.
Alphabot2 for micro:bit User Manual 4. After setting, scanning devices again. BBC micro:bit[tozug]4 is listed, then you can clock it to connect with micro:bit.
Alphabot2 for micro:bit User Manual D-PAD CONTROLLER In the App, you can find an option named Dual D-Pad Controller. Click it to enter a control page with dual D-pad (eight buttons). Click the top right three-dots icon you can change the settings. Every time virtual buttons are pressed, related signals are sent to micro:bit via Bluetooth. Gamepad events are triggered by these signals on micro:bit. Let’s do the script.
Alphabot2 for micro:bit User Manual 1. The whole script is as blow: 2. on event from … with value block can be found in Control package 3. MES_DPAD_CONTROLLER_ID is signal (the event) from APP 4. MICROBIT_EVT_ANT is the value of the event 5. MES_DPAD_CONTROLLER_ID and MICROBIT_EVT_ANY blocks can be founded in Control->More 6. Download the script and test.
Alphabot2 for micro:bit User Manual D-PAD CONTROLLER 2 In the Last script, we only use fours buttons, however, as we know, there is dual D-Pad controller in APP, which has eight buttons. We modify the last script, make micro:bit show different icon when the less four buttons are press.
Alphabot2 for micro:bit User Manual CHAPTER 9 2.4G RADIO 2.GHz radio is a wireless communication, popularly used for remote communication like intercom. To do this project, you need at least two micro:bit and one Joystick for micro:bit. ADD PACKAGE Add radio package first. RADIO COMMUNICATING Note that you should 1. You need to set the two micro:bit in one group using block radio set group 1 2.
Alphabot2 for micro:bit User Manual 3. User radio received block to receive string. 4. Download the script to both micro:bit and test 5. Expected result it that, if the buttons of one micro:bit are pressed, A or B is showed on another micro:bit.
Alphabot2 for micro:bit User Manual JOYSTICK FOR MICRO:BIT Joystick for micro:bit is a little module with one joystick and four buttons. Here we use it to control Robot via Radio. 1. Add package We provide a package for joystick for micro:bit, you can add it with this address: https://github.com/waveshare/JoyStick There are five blocks.
Alphabot2 for micro:bit User Manual module.
Alphabot2 for micro:bit User Manual 2. The script for sender: - Download this script to one micro:bit as sender, which insert to joystick module 3.
Alphabot2 for micro:bit User Manual -Download this script to another micro:bit as receiver, which insert to Alphabot2 61 / 76
Alphabot2 for micro:bit User Manual JOYSTICK FOR MICRO:BIT 2 Modify the last two scripts, make LEDs matrix show emoticons when four color buttons of joystick module are pressed 1.
Alphabot2 for micro:bit User Manual 2.
Alphabot2 for micro:bit User Manual POSTURE CONTROL In chapter 3, we have described sensors, accelerometer can be used to detect status of micro:bit, so we add the posture control part to last scripts.
Alphabot2 for micro:bit User Manual 1. Script for sender: 2. Download the script to sender and test. Robot will move when you tilt micro:bit.
Alphabot2 for micro:bit User Manual CHAPTER 10 ULTRASONIC OBSTACLE AVOIDANCING The eyes of the Alphabot2 is ultrasonic sensor, we can use it to do obstacle avoidance.
Alphabot2 for micro:bit User Manual ULTRASONIC SENSOR It is similar to the infrared sensor, ultrasonic sensor has one sender and one receiver as well. Ultrasonic sensor can detect the distances of front obstacles. Let’s create a new project to read value from ultrasonic sensor. -Ultrasonic block can be founded in AlphaBot2 package.
Alphabot2 for micro:bit User Manual OBSTACLE AVOIDING With the ultrasonic sensor, we can make Robot stop if there is obstacle in the front Robot keeps forward if the distance of obstacle in the front is longer than 15cm at the beginning. and stop when the distance is less than 15cm. Modify the late script, we can let Robot turn right if obstacle is detected.
Alphabot2 for micro:bit User Manual CHAPTER 11 LINE TRACKING In the bottom side of Alphabot2-base board, tracker sensor is integrated for tracking function.
Alphabot2 for micro:bit User Manual TRACKER SENSOR The tracker sensor helps the robot move along the black line on the ground. There are five detectors at the bottom of the sensor, and the infrared LED light is used to project infrared light to the ground to detect the deviation of the module relative to the black line. In Alphabot2 package: SensorCalibrated block is used to calibrate the sensor for accurate Min and Max value. AnalogRead block is used to read original data from infrared tacker sensor.
Alphabot2 for micro:bit User Manual ORIGINAL DATA We create a new project, to read the five value (there are five detectors) and print it to -set item to block can be founded in Variable -serial write number and serial write string blocks can be founded in Advanced->Serial -item get value at block can be founded in Advanced->Arrays 1.
Alphabot2 for micro:bit User Manual 2. Download the script to micro:bit and open serial software, set baud rate to 115200, 8N1. Data of sensors are printed to serial as below: - If you put the Alphabot2 on the air, the output values are small, about 0~10 - If you put the robot to white ground, the data will rise to 500~700 - If you put it on black line, the output are about 100.
Alphabot2 for micro:bit User Manual 3. We modify the script to output the position of black line -Download the code to micro:bit. When black line is under the tracker sensor, data are smaller to 80~100. The extreme right data is the position of black line. Note that these data are not be calibrated.
Alphabot2 for micro:bit User Manual CALIBRATED DATA We modify the last script to get calibrated data.
Alphabot2 for micro:bit User Manual -Put the robot on ground, and make sure the black line is on the center of ground. After 3s (run the code), robot begin to calibrate, turn left first, then turn right, finally turn back to original place. Calibration is done for accurate tacking data The calibrated data is outputted as below: -First line shows the max values of every sensor -Second line shows the min values of every sensor -Flowing the calibrated data.
Alphabot2 for micro:bit User Manual TRACKING We have learned how the tracker sensor work, now let’s create a new project to do the line tracking. -P is the tolerance of position. positive: robot deviation to right; negative: robot deviation to left. - D is the difference between current P and last P, bigger the D, faster the robot response.
