oooohhhhhhh... I see.
So a shift register it is.

Thanks for the clarification.

No, wait... you can write on it.

On the datasheet (http://www.datasheetcatalog.org/datasheet2/8/0uo046lw3xgikpf1d0zg15wpefpy.pdf) it says:

Code:

The 74HC/HCT4051 are 8-channel analog
multiplexers/demultiplexers with three digital select inputs
(S0to S2), an active LOW enable input (E), eight
independent inputs/outputs (Y0to Y7) and a common
input/output (Z).

What I want to do is write on 8 different pins by using the multiplexer, one at a time by writing each time the selector value and then the pin value. Am I that wrong?

oh... ok, so a multiplexer cannot be used to write?
There is the problem then, hehe. I thought it could be used for reading as well as writing.
I would need to use a shift register then, right?

Cool project by the way!

I am using an IC that has a data input of 8 bit. Instead of using 8 pins on my Arduino I want to use a multiplexer.
So I connected it in the same way it's here: http://www.arduino.cc/es_old/Tutoriales/74HC4051
but instead of doing a analogRead at the end, I do a digitalWrite to the "COM OUT/IN" pin on the multiplexer. And when trying to write a certain 8 bit value it doesn't work.

I did a test reading a control pin on the multiplexer outputs but it's not even stable, it's erratic.

Is it possible to use this multiplexer in the way I want? What's wrong????

Thanks!

I used the example for Strings documented here: http://arduino.cc/en/Reference/PROGMEM
The problem seems to be giving it a variable instead of a constant where it is "i" here:

Code:

strcpy_P(buffer, (char*)pgm_read_word(&(string_table[i])));

I really don't know why it does that, here it is used like that and it is suposed to work fine:

Code:

  for (int i = 0; i < 6; i++)
  {
    strcpy_P(buffer, (char*)pgm_read_word(&(string_table[i]))); // Necessary casts and dereferencing, just copy.
    Serial.println( buffer );
    delay( 500 );
  }

Anyway... I resolved it by putting a number instead of "i"
Thanks

now, I "commented" some of the definition lines of PROGMEM at the beginning to check if it was memory problem and also I added this on the trouble line:

Code:

  printLog("menuIndex",menuIndex); // <--- ADDED THIS
  strcpy_P(buffer, (char*)pgm_read_word(&(menuOption[noteNumb])));  //    <--- THIS LINE IS TROUBLE
  Serial.println(buffer);
  printLog("menuIndex",menuIndex); // <--- ADDED THIS

Its giving me trash on the Serial Monitor, and the programm crashes (on Arduino), it doesn't responds anymore.

I want to store a lot of strings for displaying it on an LCD, so first I do this:

Code:

prog_char string_0[] PROGMEM = "1-Tempo";
prog_char string_1[] PROGMEM = "2-Lider gordo";
prog_char string_2[] PROGMEM = "3-Envolvente";
prog_char string_3[] PROGMEM = "3b-Forma de env";
... etc etc
prog_char string_34[] PROGMEM = "C#";
prog_char string_35[] PROGMEM = "C";
prog_char string_36[] PROGMEM = "B";
prog_char string_37[] PROGMEM = "A#";
prog_char string_38[] PROGMEM = "A";

PROGMEM const char *menuOption[] = {string_0,string_1,string_2,string_3,... etc etc ,string_38};
char buffer[16];

then when I want to display one of the strings on the LCD:

Code:

strcpy_P(buffer, (char*)pgm_read_word(&(menuOption[21])));
lcd.print(buffer);

and that seems to work fine.

but when I want to return one of those strings back from a function I get a strange behavior

Code:

String getNoteName(int pitch){
  int oct = ((pitch-33)/12)+1; //33=A1
  int noteNumb = pitch-((12*(oct+2))-3);
 
  noteNumb=noteNumb+38; //Index 38 is A, 37 is A#, 36 is B and so on...
  String noteName;
  strcpy_P(buffer, (char*)pgm_read_word(&(menuOption[noteNumb])));  //    <--- THIS LINE IS TROUBLE!
  Serial.println(buffer);
  noteName = String(buffer);
  noteName.concat(oct);
  return noteName;

What that function does is you give it the note number and it returns the note name, for example "A4". The problem is that the line I point there is, somehow, changing the value for menuIndex when I do this:

Code:

  strcpy_P(buffer, (char*)pgm_read_word(&(menuOption[menuIndex])));
  Serial.println(buffer);
  lcd.print(buffer);

also when I print buffer to Serial it prints this:

œ
”œ
”œ
”œ
”œ
•œ
–Xœ
”ü”C”œ
”œ
”œ
”œ
”œ
”œ
cB6·›Ø§9hV®º«UŒ<·ÌWc½míýu>ör1”

Any idea???? Very weird, I am not writing on the memory, always reading... or that is what I intend...
Could it be that I am getting low on memory? my sketch is 19.300 bytes according to the bottom of the compiler
Thanks!

I am working on a small synth and I wanted to have one knob that detunes one oscillator from the main note.
If someone detunes it and then wants to put it back to where it was, on a normal potentiometer you will have to use your ear.
So I was thinking of having a potentiometer/knob like the one on some radios where you control the balance: When you reach the normal (center) position it clicks and goes to the exact middle, if you want to move it from the center the knob resists a little.

Could I buy it somewhere? What's called?

BONUS: Also what about ribbon resistor? A band that gets different R values depending on where you press it.

Thanks!

OH YEAH! The problem was the way I was sending the address for the registers.
I used a library for fast pin switching so I didn't have to use PORT manipulation.

Right now I reached a point where you can play a note with a button and you can change pitch of the note with a pot.

Again, thank you very much to all, especially Majenco and Telecommando for taking the time to help me!

For future generations  I will paste the entire code here:

Code:

#include <digitalWriteFast.h>
//then you can use digitalWriteFast(pin,HIGH/LOW),
//digitalReadFast(pin), pinMode(pin,INPUT/OUTPUT),
//digitalWriteFast2(pin,HIGH/LOW), digitalReadFast2(pin),
//pinMode2(pin,INPUT/OUTPUT)very much as you have used the built-in commands.
//The object code will not only be faster, but actually smaller as well.

//----CLOCK OUTPUT ON PIN 3
const int freqOutputPin = 3; 
const int ocr2aval  = 3;
const int prescale  = 1;
const float period    = 2.0 * prescale * (ocr2aval+1) / (F_CPU/1.0e6);
const float freq      = 1.0e6 / period;
//---------


const int dataPins[] = {4,5,6,7,8,9,10,11};
const int bc1Pin=12;
const int bdirPin=13;
//-------

const int pitchPin=A0;
float oldPitch=-1;
int oldPitchDec=-1;
const int playPin=A1;

void setup() {
  //---for the clock output
  pinMode(freqOutputPin, OUTPUT);
  Serial.begin(9600);
  TCCR2A = ((1 << WGM21) | (1 << COM2B0));
  TCCR2B = (1 << CS20);
  TIMSK2 = 0;
  OCR2A = ocr2aval;

  Serial.print("Period    = ");
  Serial.print(period);
  Serial.println(" microseconds");
  Serial.print("Frequency = ");
  Serial.print(freq);
  Serial.println(" Hz");
  //----
 
  pinMode (bc1Pin,OUTPUT);
  pinMode (bdirPin,OUTPUT);
  pinMode (pitchPin,INPUT);
  Serial.begin(9600);
  inactiveModeFun();
  setDataOutFun();
  resetICFun();
  testSoundA();
}

void loop() {
  float pitch = analogRead(pitchPin);
  pitch=(pitch/1023)*15;
  int pitchDec=(pitch-int(pitch))*255;
 
  if (analogRead(playPin) < 16) {
  writeICFun(13,0);
  }
 
  delay(100);
  if (int(pitch)!=int(oldPitch)) {
    oldPitch=pitch;
    Serial.print("Course: ");
    Serial.println(int(pitch));
    writeICFun(1,int(pitch));
    writeICFun(3,int(pitch));
    writeICFun(5,int(pitch));
  } 
  if (pitchDec-oldPitchDec<10 ||  pitchDec-oldPitchDec>-10){
    oldPitchDec=pitchDec;
    //Serial.print("Fine: ");
    //Serial.println(pitchDec);
    writeICFun(0,int(pitchDec));
    writeICFun(2,int(pitchDec));
    writeICFun(4,int(pitchDec));
  }
 
}

void writeICFun(int reg,int valor) { //maneja valor integer, lo convierte y lo pasa a la otra

  writeBusFun(reg); //buscar dir
  latchModeFun();
  inactiveModeFun();
  writeBusFun(valor); //darle varlor
  writeModeFun(); 
  inactiveModeFun();
}
void writeBusFun(int valor) {
  for (int x=0;x<8;x++) {
    digitalWriteFast2(dataPins[x],bitRead(valor,x));
  }
}

byte readICFun(int reg) {
  writeBusFun(reg); //buscar dir
  latchModeFun();
  inactiveModeFun();
  readModeFun();
  byte valorByte=readBusFun(); //mira valores
  inactiveModeFun();
  return valorByte;

}
byte readBusFun() {
  setDataInFun();
  byte valorByte=0;
  for (int x=0;x<8;x++) {
    bitWrite(valorByte,x,digitalRead(dataPins[x]));
  }
  setDataOutFun();
  return valorByte; 
}

void inactiveModeFun(){
  digitalWriteFast2(bdirPin,LOW);
  digitalWriteFast2(bc1Pin,LOW)
}
void readModeFun(){
  digitalWriteFast2(bdirPin,LOW);
  digitalWriteFast2(bc1Pin,HIGH)
}
void writeModeFun(){
  digitalWriteFast2(bdirPin,HIGH);
  digitalWriteFast2(bc1Pin,LOW)
}
void latchModeFun() {
  digitalWriteFast2(bdirPin,HIGH);
  digitalWriteFast2(bc1Pin,HIGH)
}
void setDataOutFun(){
  for (int x=0;x<8;x++) {
    pinMode(dataPins[x],OUTPUT);
}
}
void setDataInFun(){
  for (int x=0;x<8;x++) {
    pinMode(dataPins[x],INPUT);
}
}
void testSoundA(){
  writeICFun(0,0);
  writeICFun(1,6);
  //delay(6);
  writeICFun(2,0);
  writeICFun(3,6);
  writeICFun(4,0);
  writeICFun(5,6);
  writeICFun(6,1);
  writeICFun(7,int(B11111000));
  writeICFun(8,16);
  writeICFun(9,16);
  writeICFun(10,16);
  writeICFun(11,0);
  writeICFun(12,50);
  writeICFun(13,0);
}
void resetICFun(){
  for (int x=0;x<6;x++){
    writeICFun(x,0);
  }
}

There might be some variables named in spanish language but I changed that, so it's the minority.

[YOU KNOW WHAAAAAAT??? I tryed again with your test tone and it WORKS!!!]

Thanks a lot for that long and detailed reply, it was very helpful!!!
Now I understand why were the readings like that, so let's suppose that the clock works.

Your connections to the Arduino should be similar to Figure 11 in the data sheet, 8 data lines and 3 control. It's also possible to control the chip with only 2 control lines, see Section 2.3
Next, I would see if I could write to and read from a register. If you can't do that, there's probably something wrong either with your wiring or code.

The connections between PSG and Arduino are like that, and I already tied BC2 to +5v, so I already use only 2 control lines.

YOU KNOW WHAAAAAAT??? I tryed again with your test tone and it WORKS!!!

I will paste entire and corrected code on this post: http://arduino.cc/forum/index.php?topic=114412

Hahaha, I'm glad you took responsibility for that!
No problem, I'll try again replacing all those "1111" with "0000" on the register addresses and report back.
I saw somewhere else that the high order bits were all "1" but maybe it was something else...

I know I am asking so many things, but please be patient with me, I am new to Arduino!

I tried with a clock circuit and also with a code clock using PIN 3 of Arduino.
I get no sound from any channel, could you please take a look at this code and tell me if I am in the right direction???

On the main loop, just to test for sound on Channel A I do this:

Code:

void loop() {
  delay(3000);
  writeICFun(7,62); //Mixer: channel A only
  writeICFun(1,50); //Channel A course pitch
  writeICFun(8,15); //Volume A to max
}

To write a value to a register I use these functions:

Code:

void writeICFun(int reg,int valor) {
  //address to R01 is 11110001. If reg=1, then we need to add: 11110000 -> 240(dec)
  reg=reg+240;

  inactiveModeFun();
  Serial.println("Write on Reg number: ");
  writeBusFun(reg); //sends address of register
  latchModeFun();
  inactiveModeFun();
  Serial.println("Value to write :");
  writeBusFun(valor); //send value
  writeModeFun(); 
  inactiveModeFun();
}

void writeBusFun(int value) {
  Serial.println(value,BIN); 
  for (int x=0;x<8;x++) {
    digitalWrite(dataPins[x],bitRead(value,x));
  }
  Serial.println("-FIN Write-");
}
void inactiveModeFun(){
  digitalWrite(bdirPin,0);
  digitalWrite(bc1Pin,0);
}
void readModeFun(){
  digitalWrite(bdirPin,0);
  digitalWrite(bc1Pin,1);
}
void writeModeFun(){
  digitalWrite(bdirPin,1);
  digitalWrite(bc1Pin,0);
}
void latchModeFun() {
  digitalWrite(bdirPin,1);
  digitalWrite(bc1Pin,1);
}

Thanks a lot!

NEED HELP AGAIN!
Ok, I did the clock circuit like the one on page 29 of the Ay-3-8910 datasheet: http://www.michael-george-hart.com/articles/computerscience/AY-3-8910_8912-Programmable_Sound_Generator.pdf
Difference is that I used a 4mhz crystal, and PIN 13 (after the inverter) goes to the PSG (in order to get 1mhz) and PIN 1 goes to PIN 11 because I don't need it's 2mhz output, no other output.
Also, I used a 330ohm R (instead of 300ohm) and 22pF capacitor (instead of 20pF) but that shouldn't be a problem, right?

Now, I think it is not working, if I connect the output to an Arduino PIN and do a Serial.print(digitalRead(1)) the amount of 0's and 1's I get is not even, for instance I get:

00110001100111 and so on...

Is there another way of testing if it works?
I followed the write and read procedures as majenco told me on another post (http://arduino.cc/forum/index.php/topic,114412.0.html) but it's not working right, and of course there is no sound coming from the channels. If it's useful I could paste some code to check if it's right.

Help?? Thanksssssssss!

[I should connect PIN 13 to the PSG to get 1mhz]

Ok, that's some useful information... from what I see on the clock circuit in the AY-3-8910 datasheet, I should connect PIN 13 to the PSG to get 1mhz.
I have a 4mhz crystal, so PIN 1 should get an output of 2mhz and PIN 13 an output of 1mhz in my case.

Can't wait the store gets open so I can buy what I need! I already have some coding to test a tone.

[What if I have a 4mhz crystal? The same values of R and C should work, right?]

Oh... I never saw there was a clock circuit in the Ay-3-8910 datasheet. Its in Section 4.2 (page 29)

What if I have a 4mhz crystal? The same values of R and C should work, right?

In my case, do I need to connect PIN 13 of the CD4013 to the ground? Because I don't need a clock on my microcomputer (Arduino)

Ok, tomorrow I'll try that!

Thanks, all!