PVRADIO
From emboxit
Digital FM-Radio[1] to be used with PV
Contents
Background
Features
Gallery
<pdf>PVRADIO-1.PDF</pdf> <pdf>PVRADIO-3.pdf</pdf>
Code
Si4703_Example.pde <cpp> // NX 2011.03.15 // First evaluation of code, at O:\workspaces\arduino\si4703\Si4703_Example // DONOT USE EXTERNAL FLASH-DISK
// NX 2011.04.27 // CHECK AND REPEAT COMPILE // TODO: MAKE NOTES: WHERE .HEX IS SAVED. NOW THE INFO IS ONLY AT BOOKMARKS
// NX 2011.04.28 // READ THE SOURCE // Seems very good and simple. It would be a lot of work to understand the Si4703 without this. // To decide if seek or tune will be used on PVRADIO // TODO: Add the 4 x 7-segment Display Fuction
// NX 2011.05.02 // Arduino Loader with AVR-Studio programmer // Arduino serial Upload // FM-RADIO Worked. // At 97.3MHz with FM-Transmiter // No other station inside LAB, (like all other radios)
// NX 2011.05.03 // 1ms tick updates 7-seg display // Frequency on Display // 7-seg and timer interrupt code examples from below // http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1289095761 // http://popdevelop.com/2010/04/mastering-timer-interrupts-on-the-arduino/
/*
1-6-2011 Spark Fun Electronics 2011 Nathan Seidle This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license). To use this code, connect the following 5 wires: Arduino : Si470x board 3.3V : VCC GND : GND A5 : SCLK A4 : SDIO D2 : RST A0 : Trimpot (optional) Look for serial output at 57600bps. The Si4703 ACKs the first byte, and NACKs the 2nd byte of a read. 1/18 - after much hacking, I suggest NEVER write to a register without first reading the contents of a chip. ie, don't updateRegisters without first readRegisters. If anyone manages to get this datasheet downloaded http://wenku.baidu.com/view/d6f0e6ee5ef7ba0d4a733b61.html Please let us know. It seem to be the latest version of the programming guide. It had a change on page 12 (write 0x8100 to 0x07) that allowed me to get the chip working.. Also, if you happen to find "AN243: Using RDS/RBDS with the Si4701/03", please share. I love it when companies refer to documents that don't exist. 1/20 - Picking up FM stations from a plane flying over Portugal! Sweet! 93.9MHz sounds a little soft for my tastes,s but it's in Porteguese. ToDo: Display current status (from 0x0A) - done 1/20/11 Add RDS decoding - works, sort of Volume Up/Down - done 1/20/11 Mute toggle - done 1/20/11 Tune Up/Down - done 1/20/11 Read current channel (0xB0) - done 1/20/11 Setup for Europe - done 1/20/11 Seek up/down - done 1/25/11 The Si4703 breakout does work with line out into a stereo or other amplifier. Be sure to test with different length 3.5mm cables. Too short of a cable may degrade reception. */
- include <Wire.h>
int STATUS_LED = 13; int resetPin = 2; int SDIO = A4; //SDA/A4 on Arduino int SCLK = A5; //SCL/A5 on Arduino char printBuffer[50]; uint16_t si4703_registers[16]; //There are 16 registers, each 16 bits large
int ANODE1 = A0; int ANODE2 = A1; int ANODE3 = A2; int ANODE4 = A3;
//DIGITAL PINS int A = 3; int B= 4; int C= 5; int D = 6; int E= 7; int F= 8; int G= 9; int DP= 10;
int TUNEDN= 11; int TUNEUP= 12; int rval=0;
int i;
unsigned char count=1;
/* Timer2 reload value, globally available */
unsigned int tcnt2;
/* Toggle HIGH or LOW digital write */ int toggle = 0;
char DISP[5] = {0,1, 5, 2, 3};
int currentChannel = 973; //Default the unit to a known good local radio station
- define FAIL 0
- define SUCCESS 1
- define SI4703 0x10 //0b._001.0000 = I2C address of Si4703 - note that the Wire function assumes non-left-shifted I2C address, not 0b.0010.000W
- define I2C_FAIL_MAX 10 //This is the number of attempts we will try to contact the device before erroring out
// NX: activated below line
- define IN_EUROPE //Use this define to setup European FM reception. I wuz there for a day during testing (TEI 2011).
- define SEEK_DOWN 0 //Direction used for seeking. Default is down
- define SEEK_UP 1
//Define the register names
- define DEVICEID 0x00
- define CHIPID 0x01
- define POWERCFG 0x02
- define CHANNEL 0x03
- define SYSCONFIG1 0x04
- define SYSCONFIG2 0x05
- define STATUSRSSI 0x0A
- define READCHAN 0x0B
- define RDSA 0x0C
- define RDSB 0x0D
- define RDSC 0x0E
- define RDSD 0x0F
//Register 0x02 - POWERCFG
- define SMUTE 15
- define DMUTE 14
- define SKMODE 10
- define SEEKUP 9
- define SEEK 8
//Register 0x03 - CHANNEL
- define TUNE 15
//Register 0x04 - SYSCONFIG1
- define RDS 12
- define DE 11
//Register 0x05 - SYSCONFIG2
- define SPACE1 5
- define SPACE0 4
//Register 0x0A - STATUSRSSI
- define RDSR 15
- define STC 14
- define SFBL 13
- define AFCRL 12
- define RDSS 11
- define STEREO 8
void setup() {
pinMode(13, OUTPUT); pinMode(A0, INPUT); //Optional trimpot for analog station control pinMode(ANODE1, OUTPUT); // pinMode(ANODE2, OUTPUT); // pinMode(ANODE3, OUTPUT); // pinMode(ANODE4, OUTPUT); // pinMode(A, OUTPUT); // pinMode(B, OUTPUT); // pinMode(C, OUTPUT); // pinMode(D, OUTPUT); // pinMode(E, OUTPUT); // pinMode(F, OUTPUT); // pinMode(G, OUTPUT); // pinMode(DP, OUTPUT); // pinMode(TUNEUP,INPUT); pinMode(TUNEDN,INPUT); digitalWrite(ANODE1, HIGH); // digitalWrite(ANODE2, HIGH); // digitalWrite(ANODE3, HIGH); // digitalWrite(ANODE4, HIGH); // digitalWrite(A, LOW); // digitalWrite(B, LOW); // digitalWrite(C, LOW); // digitalWrite(D, LOW); // digitalWrite(E, LOW); // digitalWrite(F, LOW); // digitalWrite(G, LOW); // digitalWrite(DP, LOW); //
Serial.begin(57600); Serial.println();
si4703_init(); //Init the Si4703 - we need to toggle SDIO before Wire.begin takes over.
}
//************************* MAIN-LOOP*********************************************************************************************************************
void loop() {
segment(); setup_timer2(); char option; char vol = 15; //int currentChannel = 973; //Default the unit to a known good local radio station
gotoChannel(currentChannel);
while(1) {
Serial.println();
Serial.println("Si4703 Configuration");
currentChannel = readChannel(); sprintf(printBuffer, "Current station: %02d.%01dMHz", currentChannel / 10, currentChannel % 10); Serial.println(printBuffer);
- ifdef IN_EUROPE
Serial.println("Configured for European Radio");
- endif
Serial.println("1) Tune to 97.3");
Serial.println("2) Mute On/Off");
Serial.println("3) Display status");
Serial.println("4) Seek up");
Serial.println("5) Seek down");
Serial.println("6) Poll for RDS");
Serial.println("r) Print registers");
Serial.println("8) Turn GPIO1 High");
Serial.println("9) Turn GPIO1 Low");
Serial.println("v) Volume");
Serial.println("w) Tune up");
Serial.println("s) Tune down");
Serial.print(": ");
while ( digitalRead(TUNEUP) & digitalRead(TUNEDN) & (!Serial.available()) ) option = 0; if(digitalRead(TUNEUP) == 0) option='w'; if(digitalRead(TUNEDN) == 0) option='s'; if ( Serial.available() )option = Serial.read();
segment();
if(option == '1') {
Serial.println("Tune to 97.3");
currentChannel = 973;
//currentChannel = 1023;
gotoChannel(currentChannel);
}
else if(option == '2') {
Serial.println("Mute toggle");
si4703_readRegisters();
si4703_registers[POWERCFG] ^= (1<<DMUTE); //Toggle Mute bit
si4703_updateRegisters();
}
else if(option == '3') {
si4703_readRegisters();
Serial.println();
Serial.println("Radio Status:");
if(si4703_registers[STATUSRSSI] & (1<<RDSR)){
Serial.print(" (RDS Available)");
byte blockerrors = (si4703_registers[STATUSRSSI] & 0x0600) >> 9; //Mask in BLERA
if(blockerrors == 0) Serial.print (" (No RDS errors)");
if(blockerrors == 1) Serial.print (" (1-2 RDS errors)");
if(blockerrors == 2) Serial.print (" (3-5 RDS errors)");
if(blockerrors == 3) Serial.print (" (6+ RDS errors)");
}
else
Serial.print(" (No RDS)");
if(si4703_registers[STATUSRSSI] & (1<<STC)) Serial.print(" (Tune Complete)");
if(si4703_registers[STATUSRSSI] & (1<<SFBL))
Serial.print(" (Seek Fail)");
else
Serial.print(" (Seek Successful!)");
if(si4703_registers[STATUSRSSI] & (1<<AFCRL)) Serial.print(" (AFC/Invalid Channel)");
if(si4703_registers[STATUSRSSI] & (1<<RDSS)) Serial.print(" (RDS Synch)");
if(si4703_registers[STATUSRSSI] & (1<<STEREO))
Serial.print(" (Stereo!)");
else
Serial.print(" (Mono)");
byte rssi = si4703_registers[STATUSRSSI] & 0x00FF; //Mask in RSSI
Serial.print(" (RSSI=");
Serial.print(rssi, DEC);
Serial.println(" of 75)");
}
else if(option == '4') {
seek(SEEK_UP);
}
else if(option == '5') {
seek(SEEK_DOWN);
}
else if(option == '6') {
Serial.println("Poll RDS - x to exit");
while(1) {
if(Serial.available() > 0)
if(Serial.read() == 'x') break;
si4703_readRegisters();
if(si4703_registers[STATUSRSSI] & (1<<RDSR)){
Serial.println("We have RDS!");
byte Ah, Al, Bh, Bl, Ch, Cl, Dh, Dl;
Ah = (si4703_registers[RDSA] & 0xFF00) >> 8;
Al = (si4703_registers[RDSA] & 0x00FF);
Bh = (si4703_registers[RDSB] & 0xFF00) >> 8;
Bl = (si4703_registers[RDSB] & 0x00FF);
Ch = (si4703_registers[RDSC] & 0xFF00) >> 8;
Cl = (si4703_registers[RDSC] & 0x00FF);
Dh = (si4703_registers[RDSD] & 0xFF00) >> 8;
Dl = (si4703_registers[RDSD] & 0x00FF);
Serial.print("RDS: ");
Serial.print(Ah);
Serial.print(Al);
Serial.print(Bh);
Serial.print(Bl);
Serial.print(Ch);
Serial.print(Cl);
Serial.print(Dh);
Serial.print(Dl);
Serial.println(" !");
delay(40); //Wait for the RDS bit to clear
}
else {
Serial.println("No RDS");
delay(30); //From AN230, using the polling method 40ms should be sufficient amount of time between checks
}
//delay(500);
}
}
else if(option == '8') {
Serial.println("GPIO1 High");
si4703_registers[SYSCONFIG1] |= (1<<1) | (1<<0);
si4703_updateRegisters();
}
else if(option == '9') {
Serial.println("GPIO1 Low");
si4703_registers[SYSCONFIG1] &= ~(1<<0);
si4703_updateRegisters();
}
else if(option == 'r') {
Serial.println("Print registers");
si4703_printRegisters();
}
else if(option == 't') {
Serial.println("Trim pot tuning");
while(1) {
if(Serial.available())
if(Serial.read() == 'x') break;
int trimpot = 0;
for(int x = 0 ; x < 16 ; x++)
trimpot += analogRead(A0);
trimpot /= 16; //Take average of trimpot reading
Serial.print("Trim: ");
Serial.print(trimpot);
trimpot = map(trimpot, 0, 1023, 875, 1079); //Convert the trimpot value to a valid station
Serial.print(" station: ");
Serial.println(trimpot);
if(trimpot != currentChannel) {
currentChannel = trimpot;
gotoChannel(currentChannel);
}
delay(100);
}
}
else if(option == 'v') {
byte current_vol;
Serial.println();
Serial.println("Volume:");
Serial.println("+) Up");
Serial.println("-) Down");
Serial.println("x) Exit");
while(1){
if(Serial.available()){
option = Serial.read();
if(option == '+') {
si4703_readRegisters(); //Read the current register set
current_vol = si4703_registers[SYSCONFIG2] & 0x000F; //Read the current volume level
if(current_vol < 16) current_vol++; //Limit max volume to 0x000F
si4703_registers[SYSCONFIG2] &= 0xFFF0; //Clear volume bits
si4703_registers[SYSCONFIG2] |= current_vol; //Set new volume
si4703_updateRegisters(); //Update
Serial.print("Volume: ");
Serial.println(current_vol, DEC);
}
if(option == '-') {
si4703_readRegisters(); //Read the current register set
current_vol = si4703_registers[SYSCONFIG2] & 0x000F; //Read the current volume level
if(current_vol > 0) current_vol--; //You can't go lower than zero
si4703_registers[SYSCONFIG2] &= 0xFFF0; //Clear volume bits
si4703_registers[SYSCONFIG2] |= current_vol; //Set new volume
si4703_updateRegisters(); //Update
Serial.print("Volume: ");
Serial.println(current_vol, DEC);
}
else if(option == 'x') break;
}
}
}
else if(option == 'w') {
currentChannel = readChannel();
- ifdef IN_EUROPE
currentChannel += 1; //Increase channel by 100kHz
- else
currentChannel += 2; //Increase channel by 200kHz
- endif
gotoChannel(currentChannel);
}
else if(option == 's') {
currentChannel = readChannel();
- ifdef IN_EUROPE
currentChannel -= 1; //Decreage channel by 100kHz
- else
currentChannel -= 2; //Decrease channel by 200kHz
- endif
gotoChannel(currentChannel);
}
else {
Serial.print("Choice = ");
Serial.println(option);
}
}
}
//Given a channel, tune to it //Channel is in MHz, so 973 will tune to 97.3MHz //Note: gotoChannel will go to illegal channels (ie, greater than 110MHz) //It's left to the user to limit these if necessary //Actually, during testing the Si4703 seems to be internally limiting it at 87.5. Neat. void gotoChannel(int newChannel){
//Freq(MHz) = 0.200(in USA) * Channel + 87.5MHz //97.3 = 0.2 * Chan + 87.5 //9.8 / 0.2 = 49 newChannel *= 10; //973 * 10 = 9730 newChannel -= 8750; //9730 - 8750 = 980
- ifdef IN_EUROPE
newChannel /= 10; //980 / 10 = 98
- else
newChannel /= 20; //980 / 20 = 49
- endif
//These steps come from AN230 page 20 rev 0.5 si4703_readRegisters(); si4703_registers[CHANNEL] &= 0xFE00; //Clear out the channel bits si4703_registers[CHANNEL] |= newChannel; //Mask in the new channel //si4703_registers[CHANNEL] |= (1<<TUNE); //Set the TUNE bit to start si4703_registers[CHANNEL] |= 0x8000; //Set the TUNE bit to start si4703_updateRegisters();
delay(60); //Wait 60ms - you can use or skip this delay
//Poll to see if STC is set
Serial.println("Poll to see if STC is set");
i = 0;
while(i<1000) {
i++;
si4703_readRegisters();
if( (si4703_registers[STATUSRSSI] & (1<<STC)) != 0)
{
Serial.println("Tuning complete!");
break; //Tuning complete!
}
Serial.println("Tuning----");
}
si4703_readRegisters(); si4703_registers[CHANNEL] &= ~(1<<TUNE); //Clear the tune after a tune has completed si4703_updateRegisters();
//Wait for the si4703 to clear the STC as well
while(1) {
si4703_readRegisters();
if( (si4703_registers[STATUSRSSI] & (1<<STC)) == 0) break; //Tuning complete!
Serial.println("Waiting...");
}
}
//Reads the current channel from READCHAN //Returns a number like 973 for 97.3MHz int readChannel(void) {
si4703_readRegisters(); int channel = si4703_registers[READCHAN] & 0x03FF; //Mask out everything but the lower 10 bits
- ifdef IN_EUROPE
//Freq(MHz) = 0.100(in Europe) * Channel + 87.5MHz //X = 0.1 * Chan + 87.5 channel *= 1; //98 * 1 = 98 - I know this line is silly, but it makes the code look uniform
- else
//Freq(MHz) = 0.200(in USA) * Channel + 87.5MHz //X = 0.2 * Chan + 87.5 channel *= 2; //49 * 2 = 98
- endif
channel += 875; //98 + 875 = 973
return(channel);
}
//Seeks out the next available station //Returns the freq if it made it //Returns zero if failed byte seek(byte seekDirection){
si4703_readRegisters();
//Set seek mode wrap bit //si4703_registers[POWERCFG] |= (1<<SKMODE); //Allow wrap si4703_registers[POWERCFG] &= ~(1<<SKMODE); //Disallow wrap - if you disallow wrap, you may want to tune to 87.5 first
if(seekDirection == SEEK_DOWN) si4703_registers[POWERCFG] &= ~(1<<SEEKUP); //Seek down is the default upon reset else si4703_registers[POWERCFG] |= 1<<SEEKUP; //Set the bit to seek up
si4703_registers[POWERCFG] |= (1<<SEEK); //Start seek
si4703_updateRegisters(); //Seeking will now start
//Poll to see if STC is set
while(i<8) {
si4703_readRegisters();
if((si4703_registers[STATUSRSSI] & (1<<STC)) != 0)
{
Serial.print("Tuning complete!");
break; //Tuning complete!
}
Serial.print("Trying station:");
Serial.println(readChannel());
i++;
}
si4703_readRegisters(); int valueSFBL = si4703_registers[STATUSRSSI] & (1<<SFBL); //Store the value of SFBL si4703_registers[POWERCFG] &= ~(1<<SEEK); //Clear the seek bit after seek has completed si4703_updateRegisters();
//Wait for the si4703 to clear the STC as well
while(1) {
si4703_readRegisters();
if( (si4703_registers[STATUSRSSI] & (1<<STC)) == 0) break; //Tuning complete!
Serial.println("Waiting...");
}
if(valueSFBL) { //The bit was set indicating we hit a band limit or failed to find a station
Serial.println("Seek limit hit"); //Hit limit of band during seek
return(FAIL);
}
Serial.println("Seek complete"); //Tuning complete!
return(SUCCESS);
}
//To get the Si4703 inito 2-wire mode, SEN needs to be high and SDIO needs to be low after a reset //The breakout board has SEN pulled high, but also has SDIO pulled high. Therefore, after a normal power up //The Si4703 will be in an unknown state. RST must be controlled void si4703_init(void) {
Serial.println("Initializing I2C and Si4703");
pinMode(resetPin, OUTPUT);
pinMode(SDIO, OUTPUT); //SDIO is connected to A4 for I2C
digitalWrite(SDIO, LOW); //A low SDIO indicates a 2-wire interface
digitalWrite(resetPin, LOW); //Put Si4703 into reset
delay(1); //Some delays while we allow pins to settle
digitalWrite(resetPin, HIGH); //Bring Si4703 out of reset with SDIO set to low and SEN pulled high with on-board resistor
delay(1); //Allow Si4703 to come out of reset
Wire.begin(); //Now that the unit is reset and I2C inteface mode, we need to begin I2C
si4703_readRegisters(); //Read the current register set
//si4703_registers[0x07] = 0xBC04; //Enable the oscillator, from AN230 page 9, rev 0.5 (DOES NOT WORK, wtf Silicon Labs datasheet?)
si4703_registers[0x07] = 0x8100; //Enable the oscillator, from AN230 page 9, rev 0.61 (works)
si4703_updateRegisters(); //Update
Serial.println("32.768 KHz Oscilator Enabled");
delay(500); //Wait for clock to settle - from AN230 page 9
si4703_readRegisters(); //Read the current register set si4703_registers[POWERCFG] = 0x4001; //Enable the IC // si4703_registers[POWERCFG] |= (1<<SMUTE) | (1<<DMUTE); //Disable Mute, disable softmute si4703_registers[SYSCONFIG1] |= (1<<RDS); //Enable RDS
- ifdef IN_EUROPE
si4703_registers[SYSCONFIG1] |= (1<<DE); //50kHz Europe setup si4703_registers[SYSCONFIG2] |= (1<<SPACE0); //100kHz channel spacing for Europe
- else
si4703_registers[SYSCONFIG2] &= ~(1<<SPACE1 | 1<<SPACE0) ; //Force 200kHz channel spacing for USA
- endif
si4703_registers[SYSCONFIG2] &= 0xFFF0; //Clear volume bits si4703_registers[SYSCONFIG2] |= 0x0008; //Set volume to lowest-->MID=8 si4703_updateRegisters(); //Update
delay(110); //Max powerup time, from datasheet page 13
}
//Write the current 9 control registers (0x02 to 0x07) to the Si4703 //It's a little weird, you don't write an I2C addres //The Si4703 assumes you are writing to 0x02 first, then increments byte si4703_updateRegisters(void) {
Wire.beginTransmission(SI4703);
//A write command automatically begins with register 0x02 so no need to send a write-to address
//First we send the 0x02 to 0x07 control registers
//In general, we should not write to registers 0x08 and 0x09
for(int regSpot = 0x02 ; regSpot < 0x08 ; regSpot++) {
byte high_byte = si4703_registers[regSpot] >> 8;
byte low_byte = si4703_registers[regSpot] & 0x00FF;
Wire.send(high_byte); //Upper 8 bits Wire.send(low_byte); //Lower 8 bits }
//End this transmission
byte ack = Wire.endTransmission();
if(ack != 0) { //We have a problem!
Serial.print("Write Fail:"); //No ACK!
Serial.println(ack, DEC); //I2C error: 0 = success, 1 = data too long, 2 = rx NACK on address, 3 = rx NACK on data, 4 = other error
return(FAIL);
}
return(SUCCESS);
}
//Read the entire register control set from 0x00 to 0x0F void si4703_readRegisters(void){
//Si4703 begins reading from register upper register of 0x0A and reads to 0x0F, then loops to 0x00. Wire.requestFrom(SI4703, 32); //We want to read the entire register set from 0x0A to 0x09 = 32 bytes.
while(Wire.available() < 32) ; //Wait for 16 words/32 bytes to come back from slave I2C device //We may want some time-out error here
//Remember, register 0x0A comes in first so we have to shuffle the array around a bit
for(int x = 0x0A ; ; x++) { //Read in these 32 bytes
if(x == 0x10) x = 0; //Loop back to zero
si4703_registers[x] = Wire.receive() << 8;
si4703_registers[x] |= Wire.receive();
if(x == 0x09) break; //We're done!
}
}
void si4703_printRegisters(void) {
//Read back the registers si4703_readRegisters();
//Print the response array for debugging
for(int x = 0 ; x < 16 ; x++) {
sprintf(printBuffer, "Reg 0x%02X = 0x%04X", x, si4703_registers[x]);
Serial.println(printBuffer);
}
}
//------------------------------------------------------------ // THIS FUNCTION HAS THE DIFFERENT NUMBERS // AND THE DEGREE SYMBOL void letterfunction(unsigned char digit, unsigned char var) {
for(i=3;i<11;i++) // CLEAN ALL SEGMENTS
{
digitalWrite(i,HIGH);
}
digitalWrite(ANODE1,LOW);
digitalWrite(ANODE2,LOW);
digitalWrite(ANODE3,LOW);
digitalWrite(ANODE4,LOW);
if (digit == 1) digitalWrite(ANODE1,HIGH);
if (digit == 2) digitalWrite(ANODE2,HIGH);
if (digit == 3) {
digitalWrite(ANODE3,HIGH);
digitalWrite(DP,LOW);
}
if (digit == 4) digitalWrite(ANODE4,HIGH);
if (var==1){
digitalWrite(B,LOW);
digitalWrite(C,LOW);
}
if (var==2){
digitalWrite(A,LOW);
digitalWrite(B,LOW);
digitalWrite(G,LOW);
digitalWrite(E,LOW);
digitalWrite(D,LOW);
}
if (var==3){
digitalWrite(A,LOW);
digitalWrite(B,LOW);
digitalWrite(G,LOW);
digitalWrite(C,LOW);
digitalWrite(D,LOW);
}
if (var==4){
digitalWrite(F,LOW);
digitalWrite(B,LOW);
digitalWrite(G,LOW);
digitalWrite(C,LOW);
}
if (var==5){
digitalWrite(A,LOW);
digitalWrite(F,LOW);
digitalWrite(G,LOW);
digitalWrite(C,LOW);
digitalWrite(D,LOW);
}
if (var==6){
digitalWrite(A,LOW);
digitalWrite(F,LOW);
digitalWrite(E,LOW);
digitalWrite(D,LOW);
digitalWrite(C,LOW);
digitalWrite(G,LOW);
}
if (var==7){
digitalWrite(A,LOW);
digitalWrite(B,LOW);
digitalWrite(C,LOW);
}
if (var==8){
digitalWrite(A,LOW);
digitalWrite(B,LOW);
digitalWrite(C,LOW);
digitalWrite(D,LOW);
digitalWrite(E,LOW);
digitalWrite(F,LOW);
digitalWrite(G,LOW);
}
if (var==9){
digitalWrite(F,LOW);
digitalWrite(A,LOW);
digitalWrite(B,LOW);
digitalWrite(G,LOW);
digitalWrite(C,LOW);
digitalWrite(D,LOW);
}
if ( (var==0) & (digit!=1) ){
digitalWrite(A,LOW);
digitalWrite(B,LOW);
digitalWrite(C,LOW);
digitalWrite(D,LOW);
digitalWrite(E,LOW);
digitalWrite(F,LOW);
}
}
void segment(void){
letterfunction(count,count);
}
/* Setup phase: configure and enable timer2 overflow interrupt */
void setup_timer2() {
/* Configure the test pin as output */ /* First disable the timer overflow interrupt while we're configuring */ TIMSK2 &= ~(1<<TOIE2); /* Configure timer2 in normal mode (pure counting, no PWM etc.) */ TCCR2A &= ~((1<<WGM21) | (1<<WGM20)); TCCR2B &= ~(1<<WGM22); /* Select clock source: internal I/O clock */ ASSR &= ~(1<<AS2); /* Disable Compare Match A interrupt enable (only want overflow) */ TIMSK2 &= ~(1<<OCIE2A); /* Now configure the prescaler to CPU clock divided by 128 */ TCCR2B |= (1<<CS22) | (1<<CS20); // Set bits TCCR2B &= ~(1<<CS21); // Clear bit /* We need to calculate a proper value to load the timer counter. * The following loads the value 131 into the Timer 2 counter register * The math behind this is: * (CPU frequency) / (prescaler value) = 125000 Hz = 8us. * (desired period) / 8us = 125. * MAX(uint8) + 1 - 125 = 131; */ /* Save value globally for later reload in ISR */ tcnt2 = 131; /* Finally load end enable the timer */ TCNT2 = tcnt2; TIMSK2 |= (1<<TOIE2);
}
/*
* Install the Interrupt Service Routine (ISR) for Timer2 overflow.
* This is normally done by writing the address of the ISR in the
* interrupt vector table but conveniently done by using ISR() */
ISR(TIMER2_OVF_vect) {
/* Reload the timer */
TCNT2 = tcnt2;
/* Write to a digital pin so that we can confirm our timer */
//digitalWrite(A, toggle == 0 ? HIGH : LOW);
//toggle = ~toggle;
count=count+1;
if (count > 4) count = 1;
DISP[1] = currentChannel/1000;
DISP[2] = (currentChannel-1000*DISP[1])/100;
DISP[3] = (currentChannel - 1000*DISP[1] - 100*DISP[2] ) / 10;
DISP[4] = (currentChannel - 1000*DISP[1] - 100*DISP[2] - 10*DISP[3] );
letterfunction(count,DISP[count]);
}
</cpp>
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