Library for RAM chip

Using Arduino Storage
41

Now the _read() always returns 0

here is the code:

#include "AM9111.h"
#include "WProgram.h"

/////////////////////////////////////////
//
// PUBLIC
//
AM9111::AM9111(uint8_t outputDisablePin, uint8_t writeEnablePin)
{
  _odp = outputDisablePin;
  _wep = writeEnablePin;
}

int AM9111::setIO(uint8_t IO0, uint8_t IO1, uint8_t IO2, uint8_t IO3)
{
  _IO[0] = IO0;
  _IO[1] = IO1;
  _IO[2] = IO2;
  _IO[3] = IO3;
}
  

int AM9111::read(unsigned int address)
{
  int rv = 0;
  _setAddress(address);
  return rv;
}

int AM9111::write(unsigned int address, uint8_t value)
{
  int rv = 0;
  _setAddress(address);
  rv = _write(value);
  return rv;
}

/////////////////////////////////////////
//
// PRIVATE
//
void AM9111::_setAddress(unsigned int address)
{
for(int p=0; p<8; p++)
{
  pinMode(p, OUTPUT);
  digitalWrite(p, bitRead(address, p));
}
}


int AM9111::_read()
{
  digitalWrite(_odp,0);
  digitalWrite(_wep,1); 
  int rv = 0;
  bitWrite(rv,0,digitalRead(_IO[0]));
  bitWrite(rv,1,digitalRead(_IO[1]));
  bitWrite(rv,2,digitalRead(_IO[2]));
  bitWrite(rv,3,digitalRead(_IO[3]));
  return rv;
}


int AM9111::_write(uint8_t value)
{
  digitalWrite(_odp,1);
  digitalWrite(_wep,0);
  int  rv = 0;
  digitalWrite(_IO[0],bitRead(0,value));
  digitalWrite(_IO[1],bitRead(1,value));
  digitalWrite(_IO[2],bitRead(2,value));
  digitalWrite(_IO[3],bitRead(3,value));
  return rv;
}
42

is it because of the first read statement rv = 0?

43

Yes.
That, and the fact that you don't call _read from read.

44

how do you call _read from read?

45

In your own reply #30, you very nearly did.
You just got it the wrong way round.

46

I got it to work, and i just got the Shift Registers today, so i will experiment with them and add to the library.

47

I got the shift register working, but it wont work now, it keeps sending a zero

#include "AM9111_Shift.h"
#include "WProgram.h"

/////////////////////////////////////////
//
// PUBLIC
//
AM9111::AM9111(uint8_t outputDisablePin, uint8_t writeEnablePin, uint8_t clockPin, uint8_t latchPin, uint8_t dataPin)
{
  _odp = outputDisablePin;
  _wep = writeEnablePin;
  _cp = clockPin;
  _lp = latchPin;
  _dp = dataPin;
  pinMode(_lp, OUTPUT);
  pinMode(_cp, OUTPUT);
  pinMode(_dp, OUTPUT);
}

int AM9111::setIO(uint8_t IO0, uint8_t IO1, uint8_t IO2, uint8_t IO3)
{
  _IO[0] = IO0;
  _IO[1] = IO1;
  _IO[2] = IO2;
  _IO[3] = IO3;
}
  

int AM9111::read(unsigned int address)
{
  int rv = 0;
  _setAddress(address);
  return rv;
}

int AM9111::write(unsigned int address, uint8_t value)
{
  int rv = 0;
  _setAddress(address);
  rv = _write(value);
  return rv;
}

/////////////////////////////////////////
//
// PRIVATE
//
void AM9111::_setAddress(unsigned int address)
{
for(int p=0; p<8; p++)


  
  digitalWrite(_lp, LOW);
    // shift out the bits:
  shiftOut(_dp, _cp, MSBFIRST, address);  

    //take the latch pin high so the LEDs will light up:
  digitalWrite(_lp, HIGH);
    // pause before next value:
  delay(15);
}


int AM9111::_read()
{
  pinMode(_IO[0],INPUT);
  pinMode(_IO[1],INPUT);
  pinMode(_IO[2],INPUT);
  pinMode(_IO[3],INPUT);

  digitalWrite(_odp,0);
  digitalWrite(_wep,1); 
  int rv = 0;
  bitWrite(rv,0,digitalRead(_IO[0]));
  bitWrite(rv,1,digitalRead(_IO[1]));
  bitWrite(rv,2,digitalRead(_IO[2]));
  bitWrite(rv,3,digitalRead(_IO[3]));
  return rv;

}


int AM9111::_write(uint8_t value)
{
  pinMode(_IO[0], OUTPUT);  
  pinMode(_IO[1], OUTPUT);
  pinMode(_IO[2], OUTPUT);
  pinMode(_IO[3], OUTPUT);

  digitalWrite(_odp,1);
  digitalWrite(_wep,0);
  int  rv = 0;
  digitalWrite(_IO[0],bitRead(0,value));
  digitalWrite(_IO[1],bitRead(1,value));
  digitalWrite(_IO[2],bitRead(2,value));
  digitalWrite(_IO[3],bitRead(3,value));
  return rv;
}
48

it keeps sending a zero

I wonder why that is:

int AM9111::read(unsigned int address)
{
  int rv = 0;
  _setAddress(address);
  return rv;
}
49

For that matter:

int  rv = 0;

digitalWrite(_IO[0],bitRead(0,value));
  digitalWrite(_IO[1],bitRead(1,value));
  digitalWrite(_IO[2],bitRead(2,value));
  digitalWrite(_IO[3],bitRead(3,value));
  return rv;

What is the purpose of rv here? It is set to zero and you never change it.

I am guessing here you are just throwing in stuff to make compiler errors go away. Well that worked, now you have runtime errors.

50

For that matter:

Quote
Code:
int rv = 0;

That's in a "write" method.

Not sure why a "write" method would want to return a value anyway.