I would think this question has been asked thousands of times, I simply cannot find many resources on the subject.
I would like to program my Arduino Uno (ATmega328P) using Atmel Studio and the C language, minus the Arduino Libraries. What I mean by this is that I would like to write code as follows:
int main(void) {
/* set pin 5 of PORTB for output*/
DDRB |= _BV(DDB5);
while (1) {
/* set pin 5 high to turn led on */
PORTB |= _BV(PORTB5);
_delay_ms(BLINK_DELAY_MS);
/* set pin 5 low to turn led off */
PORTB &= ~_BV(PORTB5);
_delay_ms(BLINK_DELAY_MS);
}
}
Rather than code that is riddled with the oh so convenient Arduino functions. I want to get under the hood and get dirty with Arduinos!
That being said, I'm looking for any great learning sources that you may be able to offer so that I can expand my knowledge!
So far, the only somewhat useful source that I've managed to find is this page:
https://hekilledmywire.wordpress.com/2010/12/04/22/
However, the images are missing and it seems minimalistic, anyways.
Provided you are familiar with C, I recommend to
start with the AVR Libc reference
inspect iom328p.h for your processor specific definitions (located under ...\Atmel Toolchain\AVR8 GCC\Native\[#.#.####]\avr8-gnu-toolchain\avr\include\avr)
optionally, in Atmel Studio create a new ASF board project selecting device ATmega328p and inspect the sources loaded into your project folder from the "user_board" template (which anyway is a generic nearly empty set of *.h's providing space for things you may/may not need)
have the complete processor manual close to you at all times - register and bitnames found there match with the definitions in AVR libraries
Be aware that the libraries coming with Atmel Studio and the toolchain support the m328P, but the UNO board per se is not supported by the ASF. However, for basic programming you will be fine.
adding ... on PORTB
PORTB is defined in your processor's specific ...io.h (1st bullet above) which is automatically included by including <io.h> and choosing the correct processor in AVR Studio. In the library of your processor you find
#define PORTB _SFR_IO8(0x05)
Looking up the processor guide (4th bullet above) page 615 you see that PORTB is at I/O address 0x05 (q.e.d.). _SFR_IO8(..) by itself is a macro defined in <avr/sfr_defs.h> to convert from I/O to memory address (yes the lower registers are double mapped as I/O and Memory, whereby Memory address is by 0x20 higher because the lowest Memory addresses are occupied by R0 to R31).
By including <io.h> you get from the AVR library
#include <avr/io.h>
// included by io.h
// #include <avr/sfr_defs.h>
// #include <avr/portpins.h>
// #include <avr/common.h>
// #include <avr/version.h>
// #include <avr/io(your_processor).h> via processor declaration ... fuses
// #include <avr/(maybe some more).h>
All these ...h's (and some more) finally let you program in C using the register/port/pin names you find in the processor manual.
There are some more usefull libs like
#include <stdint.h> // Type definitions, e.g. uint8_t
// #include "stdint-gcc.h"
#include <avr/power.h> // clock prescaler macro
#include <avr/interrupt.h> // interrupt macros
you will find libs to support reading/writing from/to program and flash memory etc. etc.
You can do what you want but you are going to need a programmer like the Atmel-ICE, AVR Dragon, STK 500 or a AVRISP mkII. There a a few more. Atmel has a number of programers depending on your needs. There a also some 3rd party programmers that are a lot cheaper. I have the STK500 and Dragon. Love them both and they play nice with Atmel Studio 6.X.
A good learning resources is this book:
Make: AVR Programming By Elliot Williams.
Related
I'm in beginner level of learning Arduino. I want to know what programming language used in Arduino?
I've followed tutorials and tried some codes and then got outputs such as blink LED, knight_rider ,measure distance using ultrasound sensor & etc.
Here is a peice of code I learned in the tutorial for measure distance using ultrasound sensor.
`Serial.print`(inches);
`Serial.print`("in \t ");
`Serial.print`(cm);
`Serial.println`("cm");
When I searched google, It says C/C++ are used in Arduino. I have learnt Cand C#. But as far I know there is no function called println in C language. It confuse me what language is this?
From the Arduino FAQ:
Can I program the Arduino board in C? In fact, you already are; the
Arduino language is merely a set of C/C++ functions that can be called
from your code. Your sketch undergoes minor changes (e.g. automatic
generation of function prototypes) and then is passed directly to a
C/C++ compiler
From Wikipedia:
The Arduino IDE supports the languages C and C++ using special rules
of code structuring.
You can define your own functions in pretty much any programming language. That there is a function named println doesn't mean that it isn't C++ anymore.
I want to write my own code for managing an Arduino serial port (9bit serial) so I need to bypass the preprogrammed arduino ISR vector for Serial1 TX. I can do that by modifying HardwareSerial1.cpp but I dislike the fact that my code becomes non portable and a potential victim of library updates.
Do you know how to program a different ISR vector without messing into library code? I tried this in my own code to no avail:
//bypass arduino library for serial 1 and use this ISR instead
ISR(UART1_UDRE_vect)
{
9bitSerial.interrupt();
}
The following error is reported, which seems to confirm the approach doesn't work:
ISR.cpp:11:25: error: expected unqualified-id before numeric constant
ISR.cpp:in expansion of macro 'UART1_UDRE_vect'
Any clues?
The safest way, IMHO, is to copy the entire HardwareSerial class to a differently-named class. Then proceed to make your modifications. This is exactly what I did for NeoHWSerial and NeoICSerial: they are copied and renamed from HardwareSerial and AltSoftSerial.
However, all uses of Serialx (instances of HardwareSerial) in a build must be replaced with instances of your class. You won't be able to mix instances of HardwareSerial with your class (duplicate ISR errors). But that's no big deal if your class only adds behavior. Other instances that don't use 9 bits should not be affected. If you don't mind, I'd be interested in folding those changes into NeoHWSerial. I've been occasionally looking at 9-bit serial for NeoSWSerial, too.
I'm making a way of getting truly global hotkeys (I.e. emits a signal on certain inputs even when app is out of focus)
This will require different code for win vs osx vs x11. In qt creator how should I go about making this suitable for cross platform development.
Edit: I don't want to know how to do the actual code with x11, windows etc. I just want to know how I would do separate definitions for each platform.
I don't want to know how to do the actual code with x11, windows etc.
I just want to know how I would do separate definitions for each
platform.
It is convenient to do with ifdefs based on pre-defined compiler symbols e.g.:
http://sourceforge.net/p/predef/wiki/OperatingSystems/
#ifdef __linux__ // linux related, GCC has that macros
// your code and/or definitions
#endif
#if defined(__linux__) || defined(macintosh)
// your code and/or definitions
#endif
You may use OR logic there as well, as many things on Mac resemble Linux and vise versa. Mind the compiler, though, if it has that symbol. I would use OR logic with all platform symbols of applicable compilers.
If you're willing to use Qt, it has OS and compiler defines easily available for you:
#include <QtGlobal>
#if defined(Q_OS_LINUX)
// linux-specifc
#elif defined(Q_OS_WIN32) && defined(Q_CC_MSVC)
// win32 and msvc
#endif
Documentation.
I'm trying to write the control code for a custom joystick, and I cannot find any reference to what needs to be implemented to be recognized by a computer as a joystick.
I can see what things I need to have by referencing various game library APIs for using a joystick.
For example, pygame has the following methods,
init
quit
get_init
get_name
get_id
get_numaxes
get_numbuttons
etc.
My next stop is to read through the kernel for Linux's HID and joystick controlers... But this seems like a really round about way of finding this information.
I haven't worked with it, but it looks like there is some interesting information in Arduino Uno Joystick HID firmware and Arduino Uno Big Joystick HID firmware. There is also UnoJoy - I'd try that first (assuming you have an Arduino Uno or Leonardo).
I am doing a little project with an arduino ethernet board. I am new to arduino and wanted to know, whether following lcd display is compatible to my arduino or not. If it is compatible, do I need more hardware, for example cables and so on...
My Arduino Ethernet board, bought on fritzing.org:
http://shop.fritzing.org/products/fritzing-starter-kit-with-arduino-ethernet
LCD-Display which I found on dx.com:
http://dx.com/p/lcd-keypad-shield-for-arduino-duemilanove-lcd-1602-118059
Thanks in advance for any help!
In the ethernet board, pins 10-13 are reserved. The lcd-shield is using pins 4-10 (although #10 is the backlit control, so it may be possible to go without it, just having a constant backlit) - I have the lcd - keypad shield, but at home, so I cannot check that now. - look into the lcd-library to see if you can somehow define it.
That is, it is not possible to use the backlight and the ethernet at the same time. For your other question, you just stack the LCD -keypad shield on top of your arduino board, no other connections or cables are needed.
Although it may look a bit more scary, a display without a shield, eg http://dx.com/p/16-x-2-character-lcd-display-module-with-blue-backlight-121356 is not much harder to set up and it gives you more flexibility. (although, for the display I linked to, you must be able to solder in a set of pins to connect it) Another alternative is http://dx.com/p/16-x-2-character-lcd-display-module-with-blue-backlight-121356 - the latter gives you more flexibility, but poorer readability and it is a bit more work to set up the library.