Adarfruit的触摸库
之前我介绍过一个MPR121 触摸传感器模块的库【参考1】，这次再介绍另外一个实现同样功能的库，差别在于这个新的库可以从Arduino IDE中直接下载到： 国内买到的板子都是根据 Adafruit仿造的，下图就是 Adafruit的原图 引出的 12个触摸脚，还有如下控制pin:1.IRQ 可以做到按下时同时 Arduino2.SDA/SCL I2C通讯用的3.ADDR: 作用是选择I2C的地址，模块本身有下拉电阻，这里可以不接。默认地址是0x5B 4.GND 地5. 3.3V 电源6. VIN 模块本身有一个电压转换芯片，可以接入 5V运行库自带的例子，接线上只要接3.3V GND SDA SCL 四根线即可，这个库本身是用轮询的方法来处理引脚的触摸信息的。代码如下：
/*********************************************************
This is a library for the MPR121 12-channel Capacitive touch sensor
Designed specifically to work with the MPR121 Breakout in the Adafruit shop
----> https://www.adafruit.com/products/
These sensors use I2C communicate, at least 2 pins are required
to interface
Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!
Written by Limor Fried/Ladyada for Adafruit Industries.
BSD license, all text above must be included in any redistribution
**********************************************************/
#include <Wire.h>
#include "Adafruit_MPR121.h"
// You can have up to 4 on one i2c bus but one is enough for testing!
Adafruit_MPR121 cap = Adafruit_MPR121();
// Keeps track of the last pins touched
// so we know when buttons are 'released'
uint16_t lasttouched = 0;
uint16_t currtouched = 0;
void setup() {
while (!Serial); // needed to keep leonardo/micro from starting too fast!
Serial.begin(9600);
Serial.println("Adafruit MPR121 Capacitive Touch sensor test");
// Default address is 0x5A, if tied to 3.3V its 0x5B
// If tied to SDA its 0x5C and if SCL then 0x5D
if (!cap.begin(0x5A)) {
Serial.println("MPR121 not found, check wiring?");
while (1);
}
Serial.println("MPR121 found!");
}
void loop() {
// Get the currently touched pads
currtouched = cap.touched();
for (uint8_t i=0; i<12; i++) {
// it if *is* touched and *wasnt* touched before, alert!
if ((currtouched & _BV(i)) && !(lasttouched & _BV(i)) ) {
Serial.print(i); Serial.println(" touched");
}
// if it *was* touched and now *isnt*, alert!
if (!(currtouched & _BV(i)) && (lasttouched & _BV(i)) ) {
Serial.print(i); Serial.println(" released");
}
}
// reset our state
lasttouched = currtouched;
// comment out this line for detailed data from the sensor!
return;
// debugging info, what
Serial.print("\t\t\t\t\t\t\t\t\t\t\t\t\t 0x"); Serial.println(cap.touched(), HEX);
Serial.print("Filt: ");
for (uint8_t i=0; i<12; i++) {
Serial.print(cap.filteredData(i)); Serial.print("\t");
}
Serial.println();
Serial.print("Base: ");
for (uint8_t i=0; i<12; i++) {
Serial.print(cap.baselineData(i)); Serial.print("\t");
}
Serial.println();
// put a delay so it isn't overwhelming
delay(100);
}
运行结果：
需要注意的是模块的地址问题，根据DataSheet ADDR 如果接到GND，地址应该是0x5B ，但是实际上是 0x5A。参考：1. http://www.lab-z.com/mpr121/MPR121 触摸传感器模块2. https://www.adafruit.com/products/1982
这是个好东西，我正在使用TTP229做东西，可以试试这个芯片。 可惜你提供的资料地址都打不开 之前买过一个这个芯片的那种电容键盘~ 我串口监视器一直显示 not found，把add口接地接3.3V接时钟和地址线都是这句。请问是什么原因 unkindle913 发表于 2021-11-19 16:47
我串口监视器一直显示 not found，把add口接地接3.3V接时钟和地址线都是这句。请问是什么原因 ...
not found 就是无法找到芯片所以输出
检查连线或者你的芯片坏了? Zoologist 发表于 2021-11-19 19:39
not found 就是无法找到芯片所以输出
检查连线或者你的芯片坏了?
大佬，我买的是黑色的那种突破板，连线是3.3V接uno板上的3.3V，商家说默认地址是0x5A，但是我无论ADD悬空还是接地还是接时钟线或者地址线都显示 not found ；而且试了两个板子都是这个情况，删掉检测那段程序后，直接显示全部触摸。是我还应该外接上拉电阻吗，试了好几天一直没成功 unkindle913 发表于 2021-11-20 11:37
大佬，我买的是黑色的那种突破板，连线是3.3V接uno板上的3.3V，商家说默认地址是0x5A，但是我无论ADD悬空 ...
你先找一个 i2c 扫描程序试试看
https://www.lab-z.com/ai2cscan/ Zoologist 发表于 2021-11-20 19:59
你先找一个 i2c 扫描程序试试看
https://www.lab-z.com/ai2cscan/
谢谢大佬，我先试试 unkindle913 发表于 2021-11-20 22:25
谢谢大佬，我先试试
我现在买东西，如果比较偏移都是一次买两个，主要是怕坏。通常来讲，两个同时坏的可能很小。
页:
[1]