Grzegorz Kaczmarek / Mbed 2 deprecated Max7221

Fix to have load pin working with SPI1.

Dependencies:   mbed

Fork of Max7221 by Dwayne Dilbeck

Max7221.cpp@3:5abc4047af8d, 2013-08-07 (annotated)

Committer:
jakowisp
Date:
Wed Aug 07 02:34:59 2013 +0000
Revision:
3:5abc4047af8d
Parent:
MAX7221/Max7221.cpp@2:828c62cc1861
Child:
5:1f3dbf38d027
Fix Library file locations

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jakowisp 2:828c62cc1861 1 /**
jakowisp 2:828c62cc1861 2 * @file Max7221.cpp
jakowisp 2:828c62cc1861 3 * @brief This file defines the Max7221 class methods and the default values for static variables
jakowisp 2:828c62cc1861 4 *
jakowisp 2:828c62cc1861 5 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 6 *
jakowisp 2:828c62cc1861 7 * @date 8/6/2013
jakowisp 2:828c62cc1861 8 */
jakowisp 1:d8589d1f368c 9 #include "mbed.h"
jakowisp 1:d8589d1f368c 10 #include "Max7221.h"
jakowisp 1:d8589d1f368c 11
jakowisp 2:828c62cc1861 12 ///Intialize the Class static members
jakowisp 2:828c62cc1861 13 ///Devices used per SPI bus are set to ZERO
jakowisp 1:d8589d1f368c 14 int Max7221::maxInUseSPI1 = 0;
jakowisp 1:d8589d1f368c 15 int Max7221::maxInUseSPI2 = 0;
jakowisp 2:828c62cc1861 16 ///Set the static pointers to the SPI busses to NULL
jakowisp 1:d8589d1f368c 17 SPI *Max7221::spi1=NULL;
jakowisp 1:d8589d1f368c 18 SPI *Max7221::spi2=NULL;
jakowisp 2:828c62cc1861 19 ///Set the static pointers to the load signals to NULL
jakowisp 1:d8589d1f368c 20 DigitalOut *Max7221::load1=NULL;
jakowisp 1:d8589d1f368c 21 DigitalOut *Max7221::load2=NULL;
jakowisp 1:d8589d1f368c 22
jakowisp 2:828c62cc1861 23 /**
jakowisp 2:828c62cc1861 24 * Constructor. This is the default constructor
jakowisp 2:828c62cc1861 25 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 26 * @param msoi The SPI pin used as input to the device. Valid values for LPC1768 are p5 or p11
jakowisp 2:828c62cc1861 27 * @param mclk The SPI pin used as clock for the device. Valid values for LPC1768 are p7 or p13
jakowisp 2:828c62cc1861 28 * @param load The pin used to control load for the device. Any pin capable for DigitalOut can be used, but the same load pin must be used for
jakowisp 2:828c62cc1861 29 * device that share the same msoi and mclk pins
jakowisp 2:828c62cc1861 30 * @date 8/6/2013
jakowisp 2:828c62cc1861 31 */
jakowisp 1:d8589d1f368c 32 Max7221::Max7221(PinName msoi, PinName mclk, PinName load){
jakowisp 2:828c62cc1861 33 ///Determine which bus we are connecting the device to based on the MSOI pin name
jakowisp 1:d8589d1f368c 34 switch (msoi) {
jakowisp 2:828c62cc1861 35 ///If using SPI bus #1
jakowisp 1:d8589d1f368c 36 case p5: maxInUseSPI1++;
jakowisp 2:828c62cc1861 37 ///Set this insctance to pointers to the correct static pointers
jakowisp 1:d8589d1f368c 38 this->id=maxInUseSPI1;
jakowisp 1:d8589d1f368c 39 this->maxInUse=&maxInUseSPI1;
jakowisp 2:828c62cc1861 40 ///If no devices have been assigned to the SPI bus it must be initialized
jakowisp 1:d8589d1f368c 41 if (spi1 ==NULL) {
jakowisp 1:d8589d1f368c 42 spi1 = new SPI(msoi, NC, mclk);
jakowisp 1:d8589d1f368c 43 load1 = new DigitalOut(load);
jakowisp 1:d8589d1f368c 44 } else {
jakowisp 2:828c62cc1861 45 ///TODO: Check that load pin is the same for all SP2
jakowisp 1:d8589d1f368c 46 }
jakowisp 1:d8589d1f368c 47 this->max72_spi=spi1;
jakowisp 1:d8589d1f368c 48 this->load = load2;
jakowisp 1:d8589d1f368c 49 break;
jakowisp 2:828c62cc1861 50 ///If using SPI bus #2
jakowisp 1:d8589d1f368c 51 case p11: maxInUseSPI2++;
jakowisp 2:828c62cc1861 52 ///Set this insctance to pointers to the correct static pointers
jakowisp 1:d8589d1f368c 53 this->id=maxInUseSPI2;
jakowisp 1:d8589d1f368c 54 this->maxInUse=&maxInUseSPI2;
jakowisp 2:828c62cc1861 55 ///If no devices have been assigned to the SPI bus it must be initialized
jakowisp 1:d8589d1f368c 56 if (spi2 ==NULL) {
jakowisp 1:d8589d1f368c 57 spi2 = new SPI(msoi, NC, mclk);
jakowisp 1:d8589d1f368c 58 load2 = new DigitalOut(load);
jakowisp 1:d8589d1f368c 59 } else {
jakowisp 2:828c62cc1861 60 ///TODO: Check that load pin is the same for all SP2
jakowisp 1:d8589d1f368c 61 }
jakowisp 1:d8589d1f368c 62 this->max72_spi=spi2;
jakowisp 1:d8589d1f368c 63 this->load = load2;
jakowisp 1:d8589d1f368c 64 break;
jakowisp 2:828c62cc1861 65 ///If a pin not belonging to a SPI bus is used, Throw error
jakowisp 1:d8589d1f368c 66 default: error("Not a SPI port");
jakowisp 1:d8589d1f368c 67 }
jakowisp 1:d8589d1f368c 68
jakowisp 1:d8589d1f368c 69 }
jakowisp 1:d8589d1f368c 70
jakowisp 2:828c62cc1861 71 /**
jakowisp 2:828c62cc1861 72 * This method is used to write a byte of data to a specified register for only the device defined in this class instance
jakowisp 2:828c62cc1861 73 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 74 * @param reg The register to write to.
jakowisp 2:828c62cc1861 75 * @param data The value to be written.
jakowisp 2:828c62cc1861 76 * @date 8/6/2013
jakowisp 2:828c62cc1861 77 *//**
jakowisp 2:828c62cc1861 78 * This method is used to write a byte of data to a specified register for only the device defined in this class instance
jakowisp 2:828c62cc1861 79 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 80 * @param reg The register to write to.
jakowisp 2:828c62cc1861 81 * @param data The value to be written.
jakowisp 2:828c62cc1861 82 * @date 8/6/2013
jakowisp 2:828c62cc1861 83 */
jakowisp 2:828c62cc1861 84 void Max7221::Write( unsigned int reg, unsigned int data) {
jakowisp 1:d8589d1f368c 85 int c = 0;
jakowisp 1:d8589d1f368c 86 *load = LOW;
jakowisp 1:d8589d1f368c 87
jakowisp 2:828c62cc1861 88 ///if there are multiple devices sharing the SPI buss and they preceed the current device in the cascade Write a NOOP to them
jakowisp 1:d8589d1f368c 89 for ( c = *maxInUse; c > this->id; c--) {
jakowisp 1:d8589d1f368c 90 max72_spi->write(0); // no-op
jakowisp 1:d8589d1f368c 91 max72_spi->write(0); // no-op
jakowisp 1:d8589d1f368c 92 }
jakowisp 2:828c62cc1861 93 ///Write to this device registers
jakowisp 1:d8589d1f368c 94 max72_spi->write(reg); // specify register
jakowisp 2:828c62cc1861 95 max72_spi->write(data); // put data
jakowisp 1:d8589d1f368c 96
jakowisp 2:828c62cc1861 97 ///if there are multiple devices sharing the SPI buss and they follow the current device in the cascade Write a NOOP to them
jakowisp 1:d8589d1f368c 98 for ( c=this->id-1; c >= 1; c--) {
jakowisp 1:d8589d1f368c 99 max72_spi->write(0); // no-op
jakowisp 1:d8589d1f368c 100 max72_spi->write(0); // no-op
jakowisp 1:d8589d1f368c 101 }
jakowisp 1:d8589d1f368c 102 *load = HIGH;
jakowisp 1:d8589d1f368c 103 }
jakowisp 1:d8589d1f368c 104
jakowisp 2:828c62cc1861 105 /**
jakowisp 2:828c62cc1861 106 * This method is used to write an intial set off values to the device to prepare it for use.
jakowisp 2:828c62cc1861 107 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 108 * @date 8/6/2013
jakowisp 2:828c62cc1861 109 */
jakowisp 1:d8589d1f368c 110 void Max7221::Setup () {
jakowisp 2:828c62cc1861 111 // initiation of the max 7221
jakowisp 1:d8589d1f368c 112 // SPI setup: 8 bits, mode 0
jakowisp 1:d8589d1f368c 113 max72_spi->format(8, 0);
jakowisp 1:d8589d1f368c 114
jakowisp 1:d8589d1f368c 115 // going by the datasheet, min clk is 100ns so theoretically 10MHz should work...
jakowisp 1:d8589d1f368c 116 max72_spi->frequency(10*MHZ);
jakowisp 1:d8589d1f368c 117
jakowisp 2:828c62cc1861 118 Write(max7219_reg_scanLimit, 0x07); ///ENABLE all 8 digits
jakowisp 2:828c62cc1861 119 Write(max7219_reg_decodeMode, 0xff); // Turn on Code B font decode for all digits
jakowisp 2:828c62cc1861 120 Write(max7219_reg_shutdown, 0x01); // Disable shutdown mode
jakowisp 2:828c62cc1861 121 Write(max7219_reg_displayTest, 0x00); // Disable display test
jakowisp 2:828c62cc1861 122 for (int e=1; e<=8; e++) { // Write blank to all digits
jakowisp 1:d8589d1f368c 123 Write(e,0xf);
jakowisp 1:d8589d1f368c 124 }
jakowisp 2:828c62cc1861 125 Write(max7219_reg_intensity, 0x01 ); // Set the display intensity to a low level.
jakowisp 1:d8589d1f368c 126 // range: 0x00 to 0x0f
jakowisp 1:d8589d1f368c 127 }
jakowisp 1:d8589d1f368c 128
jakowisp 2:828c62cc1861 129 /**
jakowisp 2:828c62cc1861 130 * This method is used to write a byte of data to a specified register for all the devices instantiated.
jakowisp 2:828c62cc1861 131 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 132 * @param reg The register to write to.
jakowisp 2:828c62cc1861 133 * @param data The value to be written.
jakowisp 2:828c62cc1861 134 * @date 8/6/2013
jakowisp 2:828c62cc1861 135 */
jakowisp 2:828c62cc1861 136 void Max7221::WriteAll (unsigned int reg, unsigned int data) {
jakowisp 2:828c62cc1861 137 ///Write to all the devices on SPI Bus #1 first
jakowisp 1:d8589d1f368c 138 if(load1 !=NULL) {
jakowisp 1:d8589d1f368c 139 *load1 = LOW; // begin
jakowisp 1:d8589d1f368c 140 for ( int c=1; c<= maxInUseSPI1; c++) {
jakowisp 1:d8589d1f368c 141 spi1->write(reg); // specify register
jakowisp 2:828c62cc1861 142 spi1->write(data); // put data
jakowisp 1:d8589d1f368c 143 }
jakowisp 1:d8589d1f368c 144 *load1 = HIGH;
jakowisp 1:d8589d1f368c 145 }
jakowisp 2:828c62cc1861 146 ///Write to all the devices on SPI Bus #2
jakowisp 1:d8589d1f368c 147 if(load2 !=NULL) {
jakowisp 1:d8589d1f368c 148 *load2 = LOW;
jakowisp 1:d8589d1f368c 149 for ( int c=1; c<= maxInUseSPI2; c++) {
jakowisp 1:d8589d1f368c 150 spi2->write(reg); // specify register
jakowisp 2:828c62cc1861 151 spi2->write(data); // put data
jakowisp 1:d8589d1f368c 152 }
jakowisp 1:d8589d1f368c 153 *load2 = HIGH;
jakowisp 1:d8589d1f368c 154 }
jakowisp 1:d8589d1f368c 155 }
jakowisp 2:828c62cc1861 156 /**
jakowisp 2:828c62cc1861 157 * This method is used to display an integer to the specified device instance. Underflow and overflow result in '-' written to all digits
jakowisp 2:828c62cc1861 158 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 159 * @param value An integer value to display
jakowisp 2:828c62cc1861 160 * @date 8/6/2013
jakowisp 2:828c62cc1861 161 */
jakowisp 1:d8589d1f368c 162 void Max7221::WriteInt( int value ){
jakowisp 1:d8589d1f368c 163 char buffer[16];
jakowisp 1:d8589d1f368c 164
jakowisp 2:828c62cc1861 165 ///TODO:SET UPPERBOUND AND LOWERBOUND based on NUMDIGITS
jakowisp 2:828c62cc1861 166 ///Check the the INT value can be displayed and convert to a string.
jakowisp 1:d8589d1f368c 167 if (value <= UPPERBOUND && value >= LOWERBOUND) {
jakowisp 1:d8589d1f368c 168 sprintf(buffer,"%8d",value);
jakowisp 1:d8589d1f368c 169 } else {
jakowisp 1:d8589d1f368c 170 sprintf(buffer,"--------");
jakowisp 1:d8589d1f368c 171 }
jakowisp 2:828c62cc1861 172 ///In case a program changed the decode mode, set it again.
jakowisp 1:d8589d1f368c 173 Write(max7219_reg_decodeMode, 0xff);
jakowisp 1:d8589d1f368c 174 for (int i=0;i<NUMDIGITS;i++) {
jakowisp 2:828c62cc1861 175 ///For each character of the string, convert the ASCII to the datacode needed by the device
jakowisp 1:d8589d1f368c 176 switch(buffer[i]){
jakowisp 1:d8589d1f368c 177 case 0x2d: buffer[i]=0xa; break;
jakowisp 1:d8589d1f368c 178 case 0x20: buffer[i]=0xf; break;
jakowisp 1:d8589d1f368c 179 default: buffer[i]= buffer[i] & 0x0f;
jakowisp 1:d8589d1f368c 180 }
jakowisp 2:828c62cc1861 181 ///Call function to write the data for each character of the srting.
jakowisp 1:d8589d1f368c 182 Write(NUMDIGITS-i,buffer[i]);
jakowisp 1:d8589d1f368c 183 }
jakowisp 1:d8589d1f368c 184 }
jakowisp 1:d8589d1f368c 185
jakowisp 2:828c62cc1861 186 /**
jakowisp 2:828c62cc1861 187 * This method is used to display a floating point number to the specified device instance.
jakowisp 2:828c62cc1861 188 * Underflow and overflow result in '-' written to all digits. The digits after the decimal
jakowisp 2:828c62cc1861 189 * point are truncated to fit the display.
jakowisp 2:828c62cc1861 190 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 191 * @param value A float value to display
jakowisp 2:828c62cc1861 192 * @date 8/6/2013
jakowisp 2:828c62cc1861 193 */
jakowisp 1:d8589d1f368c 194 void Max7221::WriteFloat( float value ){
jakowisp 1:d8589d1f368c 195 char buffer[32];
jakowisp 1:d8589d1f368c 196 int ptr=-1,len;
jakowisp 1:d8589d1f368c 197 int i;
jakowisp 1:d8589d1f368c 198
jakowisp 1:d8589d1f368c 199 sprintf(buffer,"%f",value);
jakowisp 1:d8589d1f368c 200 len=strlen(buffer);
jakowisp 1:d8589d1f368c 201 i=len-1;
jakowisp 1:d8589d1f368c 202 while(buffer[i]==0x30) {
jakowisp 1:d8589d1f368c 203 buffer[i]='\0';
jakowisp 1:d8589d1f368c 204 i--;
jakowisp 1:d8589d1f368c 205 len--;
jakowisp 1:d8589d1f368c 206 }
jakowisp 1:d8589d1f368c 207 for( i =0; i<=len; i++) {
jakowisp 1:d8589d1f368c 208 switch(buffer[i]){
jakowisp 1:d8589d1f368c 209 case 0x2d: buffer[i]=0xa; break;
jakowisp 1:d8589d1f368c 210 case 0x20: buffer[i]=0xf; break;
jakowisp 1:d8589d1f368c 211 case 0x2e: buffer[i]=buffer[i-1] | 0x80;
jakowisp 1:d8589d1f368c 212 ptr = i-1;
jakowisp 1:d8589d1f368c 213 break;
jakowisp 1:d8589d1f368c 214 default: buffer[i]= buffer[i];
jakowisp 1:d8589d1f368c 215 }
jakowisp 1:d8589d1f368c 216 if (ptr != -1) {
jakowisp 1:d8589d1f368c 217 buffer[i-1]=buffer[i];
jakowisp 1:d8589d1f368c 218 }
jakowisp 1:d8589d1f368c 219 }
jakowisp 1:d8589d1f368c 220
jakowisp 1:d8589d1f368c 221 len=strlen(buffer);
jakowisp 1:d8589d1f368c 222 Write(max7219_reg_decodeMode, 0xff);
jakowisp 1:d8589d1f368c 223
jakowisp 1:d8589d1f368c 224 // If too large for display set to '-'
jakowisp 1:d8589d1f368c 225 if(len > NUMDIGITS && (ptr==-1 || ptr>NUMDIGITS))
jakowisp 1:d8589d1f368c 226 for (int i=0;i<NUMDIGITS;i++) {
jakowisp 1:d8589d1f368c 227 buffer[i]=0x0a;
jakowisp 1:d8589d1f368c 228 }
jakowisp 1:d8589d1f368c 229 //if number is smaller than display, fill with ' '
jakowisp 1:d8589d1f368c 230 if (len<=NUMDIGITS) {
jakowisp 1:d8589d1f368c 231 for (int i=1;i<=NUMDIGITS;i++) {
jakowisp 1:d8589d1f368c 232 if(len-i>=0) {
jakowisp 1:d8589d1f368c 233 Write(i,buffer[len-i]);
jakowisp 1:d8589d1f368c 234 } else {
jakowisp 1:d8589d1f368c 235 Write(i,0xf);
jakowisp 1:d8589d1f368c 236 }
jakowisp 1:d8589d1f368c 237 }
jakowisp 1:d8589d1f368c 238 } else {
jakowisp 1:d8589d1f368c 239 //Write out the buffer, truncating the decimal digits if larger than display
jakowisp 1:d8589d1f368c 240 for (int i=0;i<NUMDIGITS;i++) {
jakowisp 1:d8589d1f368c 241 Write(NUMDIGITS-i,buffer[i]);
jakowisp 1:d8589d1f368c 242 }
jakowisp 1:d8589d1f368c 243 }
jakowisp 1:d8589d1f368c 244 }
jakowisp 1:d8589d1f368c 245
jakowisp 2:828c62cc1861 246 /**
jakowisp 2:828c62cc1861 247 * This method is used to write an intial set off values to ALL device to prepare them for use.
jakowisp 2:828c62cc1861 248 * @author Dwayne S. Dilbeck
jakowisp 2:828c62cc1861 249 * @date 8/6/2013
jakowisp 2:828c62cc1861 250 */
jakowisp 1:d8589d1f368c 251 void Max7221::SetupAll () {
jakowisp 1:d8589d1f368c 252 // initiation of the max 7219
jakowisp 1:d8589d1f368c 253 // SPI setup: 8 bits, mode 0
jakowisp 1:d8589d1f368c 254 if(spi1!=NULL) {
jakowisp 1:d8589d1f368c 255 spi1->format(8, 0);
jakowisp 1:d8589d1f368c 256 spi1->frequency(10*MHZ);
jakowisp 1:d8589d1f368c 257 }
jakowisp 1:d8589d1f368c 258 if(spi2!=NULL) {
jakowisp 1:d8589d1f368c 259 spi2->format(8, 0);
jakowisp 1:d8589d1f368c 260 spi2->frequency(10*MHZ);
jakowisp 1:d8589d1f368c 261 }
jakowisp 1:d8589d1f368c 262 WriteAll(max7219_reg_scanLimit, 0x07);
jakowisp 1:d8589d1f368c 263 WriteAll(max7219_reg_decodeMode, 0xff); // using an led matrix (not digits)
jakowisp 1:d8589d1f368c 264 WriteAll(max7219_reg_shutdown, 0x01); // not in shutdown mode
jakowisp 1:d8589d1f368c 265 WriteAll(max7219_reg_displayTest, 0x00); // no display test
jakowisp 1:d8589d1f368c 266 for (int e=1; e<=8; e++) { // empty registers, turn all LEDs off
jakowisp 1:d8589d1f368c 267 WriteAll(e,0xf);
jakowisp 1:d8589d1f368c 268 }
jakowisp 1:d8589d1f368c 269 WriteAll(max7219_reg_intensity, 0x01 & 0x0f); // the first 0x0f is the value you can set
jakowisp 1:d8589d1f368c 270 // range: 0x00 to 0x0f
jakowisp 1:d8589d1f368c 271 }
jakowisp 2:828c62cc1861 272