Rahul Maran
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MPR121_Demo
a
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Diff: mpr121.cpp
- Revision:
- 0:e09703934ff4
diff -r 000000000000 -r e09703934ff4 mpr121.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mpr121.cpp Wed Mar 16 01:49:13 2011 +0000 @@ -0,0 +1,221 @@ +/* +Copyright (c) 2011 Anthony Buckton (abuckton [at] blackink [dot} net {dot} au) + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +THE SOFTWARE. +*/ + +#include <mbed.h> +#include <sstream> +#include <string> +#include <list> + +#include <mpr121.h> + +Mpr121::Mpr121(I2C *i2c, Address i2cAddress) +{ + this->i2c = i2c; + + address = i2cAddress; + + // Configure the MPR121 settings to default + this->configureSettings(); +} + + +void Mpr121::configureSettings() +{ + // Put the MPR into setup mode + this->write(ELE_CFG,0x00); + + // Electrode filters for when data is > baseline + unsigned char gtBaseline[] = { + 0x01, //MHD_R + 0x01, //NHD_R + 0x00, //NCL_R + 0x00 //FDL_R + }; + + writeMany(MHD_R,gtBaseline,4); + + // Electrode filters for when data is < baseline + unsigned char ltBaseline[] = { + 0x01, //MHD_F + 0x01, //NHD_F + 0xFF, //NCL_F + 0x02 //FDL_F + }; + + writeMany(MHD_F,ltBaseline,4); + + // Electrode touch and release thresholds + unsigned char electrodeThresholds[] = { + E_THR_T, // Touch Threshhold + E_THR_R // Release Threshold + }; + + for(int i=0; i<12; i++){ + int result = writeMany((ELE0_T+(i*2)),electrodeThresholds,2); + } + + // Proximity Settings + unsigned char proximitySettings[] = { + 0xff, //MHD_Prox_R + 0xff, //NHD_Prox_R + 0x00, //NCL_Prox_R + 0x00, //FDL_Prox_R + 0x01, //MHD_Prox_F + 0x01, //NHD_Prox_F + 0xFF, //NCL_Prox_F + 0xff, //FDL_Prox_F + 0x00, //NHD_Prox_T + 0x00, //NCL_Prox_T + 0x00 //NFD_Prox_T + }; + writeMany(MHDPROXR,proximitySettings,11); + + unsigned char proxThresh[] = { + PROX_THR_T, // Touch Threshold + PROX_THR_R // Release Threshold + }; + writeMany(EPROXTTH,proxThresh,2); + + this->write(FIL_CFG,0x04); + + // Set the electrode config to transition to active mode + this->write(ELE_CFG,0x0c); +} + +void Mpr121::setElectrodeThreshold(int electrode, unsigned char touch, unsigned char release){ + + if(electrode > 11) return; + + // Get the current mode + unsigned char mode = this->read(ELE_CFG); + + // Put the MPR into setup mode + this->write(ELE_CFG,0x00); + + // Write the new threshold + this->write((ELE0_T+(electrode*2)), touch); + this->write((ELE0_T+(electrode*2)+1), release); + + //Restore the operating mode + this->write(ELE_CFG, mode); +} + + +unsigned char Mpr121::read(int key){ + + unsigned char data[2]; + + //Start the command + i2c->start(); + + // Address the target (Write mode) + int ack1= i2c->write(address); + + // Set the register key to read + int ack2 = i2c->write(key); + + // Re-start for read of data + i2c->start(); + + // Re-send the target address in read mode + int ack3 = i2c->write(address+1); + + // Read in the result + data[0] = i2c->read(0); + + // Reset the bus + i2c->stop(); + + return data[0]; +} + + +int Mpr121::write(int key, unsigned char value){ + + //Start the command + i2c->start(); + + // Address the target (Write mode) + int ack1= i2c->write(address); + + // Set the register key to write + int ack2 = i2c->write(key); + + // Read in the result + int ack3 = i2c->write(value); + + // Reset the bus + i2c->stop(); + + return (ack1+ack2+ack3)-3; +} + + +int Mpr121::writeMany(int start, unsigned char* dataSet, int length){ + //Start the command + i2c->start(); + + // Address the target (Write mode) + int ack= i2c->write(address); + if(ack!=1){ + return -1; + } + + // Set the register key to write + ack = i2c->write(start); + if(ack!=1){ + return -1; + } + + // Write the date set + int count = 0; + while(ack==1 && (count < length)){ + ack = i2c->write(dataSet[count]); + count++; + } + // Stop the cmd + i2c->stop(); + + return count; +} + + +bool Mpr121::getProximityMode(){ + if(this->read(ELE_CFG) > 0x0c) + return true; + else + return false; +} + +void Mpr121::setProximityMode(bool mode){ + this->write(ELE_CFG,0x00); + if(mode){ + this->write(ELE_CFG,0x30); //Sense proximity from ALL pads + } else { + this->write(ELE_CFG,0x0c); //Sense touch, all 12 pads active. + } +} + + +int Mpr121::readTouchData(){ + return this->read(0x00); +} \ No newline at end of file