decarvalho adelino / Mcp4921Lib

Library to control the 12 Bits Analog Digital Converter MCP4921

Mcp4921.cpp@0:38e03f9fa18a, 2013-11-15 (annotated)

Committer:
adelino
Date:
Fri Nov 15 14:53:04 2013 +0000
Revision:
0:38e03f9fa18a
Library to control the analog digital converter; MCp4921

Who changed what in which revision?

UserRevisionLine numberNew contents of line
adelino 0:38e03f9fa18a 1 #include "Mcp4921.h"
adelino 0:38e03f9fa18a 2
adelino 0:38e03f9fa18a 3 Mcp4921::Mcp4921(PinName _mosi,PinName _sck,PinName _cs, int _frequency):mySPI(_mosi,NC,_sck),myCs(_cs)
adelino 0:38e03f9fa18a 4 {
adelino 0:38e03f9fa18a 5 myFrequency=_frequency;
adelino 0:38e03f9fa18a 6
adelino 0:38e03f9fa18a 7 setup();
adelino 0:38e03f9fa18a 8 }
adelino 0:38e03f9fa18a 9 //---------------------------------------
adelino 0:38e03f9fa18a 10 int Mcp4921::getFrequency(void)
adelino 0:38e03f9fa18a 11 {
adelino 0:38e03f9fa18a 12 return myFrequency;
adelino 0:38e03f9fa18a 13 }
adelino 0:38e03f9fa18a 14 //--------------------------------------
adelino 0:38e03f9fa18a 15 void Mcp4921::write(int dataIntNum)
adelino 0:38e03f9fa18a 16 {
adelino 0:38e03f9fa18a 17 //valid input values are 0 - 4095. 4096 should scale to Vref.
adelino 0:38e03f9fa18a 18 char i=0;
adelino 0:38e03f9fa18a 19
adelino 0:38e03f9fa18a 20 if(dataIntNum >4095)
adelino 0:38e03f9fa18a 21 dataIntNum=4095;
adelino 0:38e03f9fa18a 22
adelino 0:38e03f9fa18a 23 if(dataIntNum <0)
adelino 0:38e03f9fa18a 24 dataIntNum=0;
adelino 0:38e03f9fa18a 25
adelino 0:38e03f9fa18a 26 int16_t temp=0;
adelino 0:38e03f9fa18a 27 temp=dataIntNum | 0x7000;
adelino 0:38e03f9fa18a 28
adelino 0:38e03f9fa18a 29 myCs=0;
adelino 0:38e03f9fa18a 30 for(i=0; i<50; i++);
adelino 0:38e03f9fa18a 31 mySPI.write(temp);
adelino 0:38e03f9fa18a 32
adelino 0:38e03f9fa18a 33 for(i=0; i<50; i++);
adelino 0:38e03f9fa18a 34 myCs=1;
adelino 0:38e03f9fa18a 35 }
adelino 0:38e03f9fa18a 36 //--------------------------------------
adelino 0:38e03f9fa18a 37 void Mcp4921::write_mV(int millivolt){
adelino 0:38e03f9fa18a 38
adelino 0:38e03f9fa18a 39 if(millivolt >3300)
adelino 0:38e03f9fa18a 40 millivolt=3300;
adelino 0:38e03f9fa18a 41
adelino 0:38e03f9fa18a 42 if(millivolt <0)
adelino 0:38e03f9fa18a 43 millivolt=0;
adelino 0:38e03f9fa18a 44
adelino 0:38e03f9fa18a 45 int val=(millivolt*4095)/3300;
adelino 0:38e03f9fa18a 46
adelino 0:38e03f9fa18a 47 write(val);
adelino 0:38e03f9fa18a 48 }
adelino 0:38e03f9fa18a 49 //--------------------------------------
adelino 0:38e03f9fa18a 50 void Mcp4921::write(float dataFloat)
adelino 0:38e03f9fa18a 51 {
adelino 0:38e03f9fa18a 52 //valid input values are 0.0 - 1.0 with 1.0 should scale to Vref.
adelino 0:38e03f9fa18a 53 if(dataFloat >1.0)
adelino 0:38e03f9fa18a 54 dataFloat=1.0;
adelino 0:38e03f9fa18a 55
adelino 0:38e03f9fa18a 56 if(dataFloat <0)
adelino 0:38e03f9fa18a 57 dataFloat=0;
adelino 0:38e03f9fa18a 58
adelino 0:38e03f9fa18a 59 float temp=4095*dataFloat;
adelino 0:38e03f9fa18a 60
adelino 0:38e03f9fa18a 61 write((int)temp);
adelino 0:38e03f9fa18a 62 }
adelino 0:38e03f9fa18a 63 //--------------------------------------
adelino 0:38e03f9fa18a 64 void Mcp4921::operator=(int dataIntNum)
adelino 0:38e03f9fa18a 65 {
adelino 0:38e03f9fa18a 66 write(dataIntNum);
adelino 0:38e03f9fa18a 67 }
adelino 0:38e03f9fa18a 68 //--------------------------------------
adelino 0:38e03f9fa18a 69 void Mcp4921::operator=(float dataFloat)
adelino 0:38e03f9fa18a 70 {
adelino 0:38e03f9fa18a 71 write(dataFloat);
adelino 0:38e03f9fa18a 72 }
adelino 0:38e03f9fa18a 73 //--------------------------------------
adelino 0:38e03f9fa18a 74 void Mcp4921::setup(void)
adelino 0:38e03f9fa18a 75 {
adelino 0:38e03f9fa18a 76 myCs=1;
adelino 0:38e03f9fa18a 77 mySPI.frequency(myFrequency); //
adelino 0:38e03f9fa18a 78 mySPI.format(16,0); //16 bits + mode 0
adelino 0:38e03f9fa18a 79 }
adelino 0:38e03f9fa18a 80 //