Add SPI.h to custom Arduino Library

[tomshirvo]

Hi All,

Making a custom library for a SPI flash Chip I have. I got it all working with Arduino just using functions. I am now trying to make my first library and I am trying to include SPI.h but it comes up saying can't file file.

It might be a little rough at the moment but it is because I am learning. If you can give me any pointers about what I have done I would very much appreciate it.

I have tried to include the SPI.h in both .h and .cpp files but doesn't work. I need to be able to call SPI.begin and SPI.transfer functions in this library.

my .h file

Code: [Select]

#ifndef flashMemory_h
#define flashMemory_h



#if defined(__AVR__)
#include "Arduino.h"
#include "hardware/avr/HW_AVR_defines.h"
#elif defined(__arm__)
#include "Arduino.h"
#include "hardware/arm/HW_ARM_defines.h"
#endif

class flashMemory
{
public:
    flashMemory(uint8_t CE);
    flashMemory(uint8_t CE,uint8_t SPIClock);
    void    begin();
    boolean    bulkErase();
    boolean    writeEnable();
    boolean    writeDisable();
    boolean    verifySR(uint8_t sRegister, uint8_t value);
    void       timeOut(uint16_t timeOut);
  protected:
    uint8_t   _pinCE, _SPIClock; 
    uint16_t  _timeOut;
    boolean   _SPIClockSelect;
    void   _SPIstart(uint8_t rate);

};

#endif
my cpp file

Code: [Select]

#include "flashMemory.h"


#if defined(__AVR__)
#include "hardware/avr/HW_AVR.h"
#elif defined(__arm__)
#include "hardware/arm/HW_ARM.h"
#endif

flashMemory::flashMemory(uint8_t CE)
{
  _SPIClockSelect = false;
_pinCE = CE;
}

flashMemory::flashMemory(uint8_t CE, uint8_t SPIClock)
{
  _SPIClockSelect = true;
_pinCE = CE;
  _SPIClock = SPIClock;
}

void flashMemory::begin()
{
    if(_SPIClockSelect)
    {
      _SPIstart(_SPIClock);
    }else
    _SPIstart(SPI_CLOCK_DEFAULT);
}


boolean flashMemory::bulkErase()
{
  writeEnable();
  digitalWrite(_pinCE,LOW);
  SPI.transfer(0xC7);
  digitalWrite(_pinCE,HIGH);
  uint32_t start = millis();
  boolean error = false;
  while(error = verifySR(0,1) == true && millis() - start < _timeOut){
  }
  return error;
}


void flashMemory::timeOut(uint16_t timeOut)
{
  _timeOut = timeOut;
}


//Write Enable
//This enables data to be send to the Flash chip to write data.
boolean flashMemory::writeEnable(void){
  uint32_t time = millis();
  boolean error = false;
  do{
    digitalWrite(_pinCE,LOW); //Select the Flash chip on the SPI bus
    SPI.transfer(0x06); //WREN (Write Enable)
    digitalWrite(_pinCE,HIGH); //deselect the Flash chip on the SPI bus
  }while(error = verifySR(1,1) == false && millis() - time < _timeOut); //Retry until the change was made
  return error;
}

//Write Disable
//This disables data to be send to the Flash chip to write data.
boolean flashMemory::writeDisable(){
  uint32_t time = millis();
  boolean error = false;
  do{
    digitalWrite(_pinCE,LOW); //Select the Flash chip on the SPI bus
    SPI.transfer(0x04); ///WRDI (Write Disable)
    digitalWrite(_pinCE,HIGH); //deselect the Flash chip on the SPI bus
  }while(error = verifySR(1,1) == false && millis() - time < _timeOut); //Retry until the change was made
  return error;
}

//Verify Status Register
//Send the register location and the value you are expecting.
//This will return a boolean for the result
boolean flashMemory::verifySR(byte sRegister, byte value){
  uint32_t time = millis();
  byte error = 0; //Hold the returned value from the status register.
  do{
    digitalWrite(_pinCE,LOW); //Select the Flash chip on the SPI bus
    SPI.transfer(0x05); //Send the status register read instruction
    error = SPI.transfer(0xff); //Read the returned data from the chip
    if(error == 255){ //If error code is 255 then show user in serial monitor

    }
    digitalWrite(_pinCE,HIGH); //deselect the Flash chip on the SPI bus
  }while(error == 255 && millis() - time < _timeOut); //do it once and if error do it until no error.
  byte _value = 0; //The value collected in the required register position
  _value = bitRead(error,sRegister); //get the value returned in that position
  if(_value != value){ //return if it was the correct response or not.
    return false;
  }else if(_value == value){
    return true;
  }
}

[sleemanj]

The Arduino IDE messes about with includes, effectively, it pre-processes your code before compiling, and inserts various stuff, creating a source code tree in a (usually temporary) folder which it then compiles, the libraries which the IDE chooses to put into the source code tree depend on what it detects is being used (by way of includes), it's all pretty brittle if you ask me, but anyway. 

As a result, what you think (as a C programmer) should work, may or may not do what you think it should be doing when the Arduino IDE has done with it.   In the IDE's "preferences.txt" file (if you open the Preferences dialog in the IDE it tells you where this is) there is an option "build.path" (this is not exposed in the GUI, you have to edit the file), set this to some specific path, reload the IDE, then compile your sketch, once done (regardless if successful or not) you can have a look at what the IDE slapped together and actually tried to compile in your specified path.

From memory (and I might be misremembering), I don't think you can actually include one library (SPI in this case) from inside another library's library code, I don't think the IDE looks deep enough to include the depended upon library in the temporary source code tree for compilation.  The typical way to do it is, to include the depended library from within the example sketches you provide with the library themselves, ie, at the same place you include your library itself.  This isn't TOO bad a solution, because most people using the Arduino IDE are just going to copy-paste your example(s) to use as a boilerplate anyway.

[tomshirvo]

Thanks for the replay.

The only problem is that I can't use the spi.transfer doesn't work in my library. So it sounds like I can't use SPI in libraries.

[Tac Eht Xilef]

The only problem is that I can't use the spi.transfer doesn't work in my library. So it sounds like I can't use SPI in libraries.

You can use spi.transfer in your own libraries - I've literally just now finished writing a library that uses it. You just can't can't just include the SPI library in your library for the reasons sleemanj mentioned; you have to #include it in your main sketch too.

Yes, it is a bit of a dumb limitation to someone coming from proper C, but it does make a twisted sort of sense in Arduino-land (if you google around you'll see some of their arguments).

(edit, as noted.)

[zapta]

How do you install your library, using the Arduino IDE Add Library? If so, they the manual way as explained in this link. It puts the library in a different location.

https://code.google.com/p/u8glib/wiki/u8glib

As others said, Arduino libraries are problematic.

[dannyf]

The complexity of managing a multi file project in the arduino ide is something that should be addressed. A typical avr or pic project for me has 20 - 30 modules - .c and .h files and to manually open them up in the arduono ide to use them in the project is just tedious.

[Tac Eht Xilef]

How do you install your library, using the Arduino IDE Add Library? If so, they the manual way as explained in this link. It puts the library in a different location.

https://code.google.com/p/u8glib/wiki/u8glib

As others said, Arduino libraries are problematic.

At least in 1.0.5/1.0.6, both ways end up sticking the library in the same place - in /[document_path]/Arduino/libraries/[library_name]. The only other valid library path in the Arduino environment is wherever the Arduino system libs (e.g. Arduino.h) are installed, which is O/S-dependent.

FWIW, a passably-OK explanation of how to use other libraries in your library can be found here (no connection, just found it on a quick google).

[tomshirvo]

So even adding the #include <SPI.h> in the sketch didn't work.

I then tried to put it in the flashMemory.h file in the below location and it worked after that.

Code: [Select]

#if defined(__AVR__)
#include "Arduino.h"
  #include "SPI.h"
#include "hardware/avr/HW_AVR_defines.h"
#elif defined(__arm__)
#include "Arduino.h"
  #include "SPI.h"
#include "hardware/arm/HW_ARM_defines.h"
#endif
Thanks for all the help.

[Tac Eht Xilef]

Sorry, I just realised my post last night wasn't clear (it was late!) - you need to include SPI.h in both the sketch & your library. I've edited it to make it clearer.

Glad you got it sorted.

[djacobow]

This. That's the brain damage of the Ard environment. Includes in libraries and other files in your sketch will mysteriously not find certain headers (mostly from "standard" Ard libraries) that are not also included in the main sketch.

Why? I dunno. Not a good reason, I'm sure.

I'm all for Ard being simple and all, but certain things they do to make life easier actually make it weirder. I'm no fan of setup() and loop(). main() is just fine, thanks. I can make my own setup and loop if I need them. Oh, and the pre-declared objects for things like Serial just bug me. Sure, it saves the beginner from having to write one mysterious line of code, but it also inhibits them from learning how stuff works.

Sorry, I just realised my post last night wasn't clear (it was late!) - you need to include SPI.h in both the sketch & your library. I've edited it to make it clearer.

Glad you got it sorted.

[westfw]

Why?

Because the IDE scans the include statements in the .ino files, and uses that information to build a set of "-I /long/path/to/librarydirectory" options for the compile line.  It doesn't do that pre-processing for .cpp or .c files, so things included only by library .cpp files don't have their paths added to the command line.

It would certainly be nice if the top-level library directories were also put in the search path, so you could do things like:
#include "SPI/spi.h" instead of #include "/Applications/arduino/Arduino-1.0.6.app/Contents/Resources/Java/libraries/SPI/spi.h"

Note that the default behavior is to require that YOU manually specify the full path, and the Ard IDE's actions are not significantly different than other IDEs that would have you set up library dependencies from some menu...

[djacobow]

It would certainly be nice if the top-level library directories were also put in the search path, so you could do things like:
#include "SPI/spi.h" instead of #include "/Applications/arduino/Arduino-1.0.6.app/Contents/Resources/Java/libraries/SPI/spi.h"

Uh huh. If they wanted to be really fancy, they could even provide a library "install" facility, where you click a menu option, point the IDE at a zip file and, voila, files are just magically copied to the right places in <sketchbook>/libraries and those include paths are automatically searched. The problem is that the IDE needs to know to rebuild the .cpp files, too, hence the scanning. But they could just scan all your project files, or else provide a checkbox list of "features" to include, like most other IDEs.

The odd think about Ard is that they have not really made serious progress in the IDE in years.

Note that the default behavior is to require that YOU manually specify the full path, and the Ard IDE's actions are not significantly different than other IDEs that would have you set up library dependencies from some menu...

But the Ard folks started with a mission to make something easy and accessible, so I think it's perfectly reasonable to hold them to a higher standard of simplicity.

[westfw]

But the Ard folks started with a mission to make something easy

For the "sketch" writers.  If you're writing libraries, you're expected to put up with more demanding requirements.

Personally, I am pretty sure that I don't want to compile every library I've ever installed, for each sketch.

Modern "professional" IDEs seem to be starting to copy all library files 'checked' into each project that uses them.  While I appreciate the benefits from a version control perspective, I don't think I like this very much either :-(

Whatever.  I have now asked: https://github.com/arduino/Arduino/issues/2448

The odd think about Ard is that they have not really made serious progress in the IDE in years.

Whereas, in a similar time interval, MPLAB became MPLABX, AVR Studio became Atmel Studio, and CCS became Eclipse-based; massive improvements that everyone is just thoroughly enthusiastic about? :-)

Also, it's not true.  There have been pretty substantial changes in the Arduino IDE "recently."  Being able to install third party libraries (and boards/etc) in the user documents/Arduino/ folder instead of deep inside the IDE install was one of them, but there's also the "variants" modification in 1.0 that allows support of significantly different AVRs, and the "platforms" modification in 1.5 that allows support of other entirely different processors.

[djacobow]

Personally, I am pretty sure that I don't want to compile every library I've ever installed, for each sketch.

Actually, with a proper make facility or something like ccache, it could be pretty painless. And really, the libraries do not need to be compiled for every sketch, but they do need to be compiled for every variant and platform. That could be done at install time.

I've never dug unto it, but the Ard environment doesn't even seem to track dependencies at all. At least on Windows, it seems to rebuild everything each time. I think on Linux it seems a bit smarter, but I haven't paid close attention.

Modern "professional" IDEs seem to be starting to copy all library files 'checked' into each project that uses them.  While I appreciate the benefits from a version control perspective, I don't think I like this very much either :-(

Yeah, I'm no fan of that, either, but I get it.

The odd think about Ard is that they have not really made serious progress in the IDE in years.

Whereas, in a similar time interval, MPLAB became MPLABX, AVR Studio became Atmel Studio, and CCS became Eclipse-based; massive improvements that everyone is just thoroughly enthusiastic about? :-)

Also, it's not true.  There have been pretty substantial changes in the Arduino IDE "recently." 

Oh, they've made improvements. But there have been really few releases. 1.0.x is still officially current, 1.5.x has been in beta for what seems like years, maybe actual years?

But the things that continue to bug me are the feeble text editor, half-baked syntax highlighting, atrocious and non-changeable font. (my eyes are failing prematurely and l's and 1's look the same to me). There are some really good monospace fonts out there for programming these days.

It also drives me bonkers that they close the serial window every time you upload. If you are using serial for upload, then, ok, how about disconnecting the serial monitor and reconnecting it after the upload? And if you are using a programmer to upload, then you can just leave it be.

But it's free and I use it all the time for AVR work because the unzip-and-run convenience is pretty hard to beat. People complains about the Ard functions, but there's nobody forcing you to use them.

[westfw]

atrocious and non-changeable font.

They're changeable.  Just not "easily."  You have to manually edit the relevant preferences and/or "theme" files.

[Mechatrommer]

sure you already or will found the solution long time ago, only if...
1) you dont insist on running things on "linux"...
2) you choose to become arduino the "IDE" developement team, not just a mere user.
arduino the "IDE" is an inevitable crap. a broken system that is well maintained and supported by many people... how irony...

*broken in the sense that the compile time is exponential compared to other IDE, thats the most killing aspect. and managing mega project many files problem is the second... imho, and this library problem? this is probably the third or forth or fifth.. small problem... small problem...