I am a begineer in learning Device Driver.I am practising with simple example to learn device driver. Can anyone suggest me how to start writing uart ,GPIO device driver for raspberry pi,because i started practising with raspberry pi only.
Thanks in advance
Regards,
pradeep
If this is your very first driver, start with something simple. I would take the following steps:
Write a simple character device driver that implements read/write/open/close file ops. That means they can be used with 'cat' and 'echo'.
Based on the initial work from 1, you can write a GPIO driver. This should be simple because all you need to do is write or read a 0 or 1 from a specific memory address.
Now that you have some experience with device drivers you can write a tty driver for your uart. There are lots of examples of tty drivers in linux already.
Related
I have got Arduino MEGA 2560. What I would like to do is to send a signal to Arduino via serial port to light specified LED up. However, I cannot find any documentation about this. What steps should I follow?
I think first, I need to compile the driver of Arduino and add it to Linux kernel. Second, I have to find some header files to use them in module. Then, I have to find functions to start serial communication and to light LEDs up. However, these are just my thoughts.
Any advice will be appreciated.
The arduino-mega (the one with ATmega2560) documentation is here:
https://www.arduino.cc/en/Main/ArduinoBoardMega2560#documentation
The serial communication via UART:
https://www.arduino.cc/en/Reference/SoftwareSerial
Since there are other ways for serial communication with the ATmega please read the documentation [above] and compare that to your exercise sheet.
I think such a kernel module is already available - and used by the arduino-ide.
I am programming a MAX32 Micro controller in MPLAB. I want to use the UART protocol to interact with my terminal (I am developing on a mac). Is this possible? Can someone point me in the right direction to get started?
Read Wikipedia UART Article
Read Reference Manual of your µC, Chapter "...UART..."
Get example Code for this issue from your Reference Manual or Programming Manual or Internet Articles
Program your board
Connect your Board with your PC via Cable (USB, RS232 to USB (virtual RS232) or UART to USB)
Open Terminal Program i.e. TeraTerm
Check your Settings i.e. Baud Rate
Try it
I have written a simple character driver.Now I want to write a UART driver for a omap 4460
processor.
In what way I should start ie how should I relate it with the character driver?
I dont know where to start.I have gone through the manual of the processor and know the functionality of the driver.Please provide me some steps
How can I communicate with an mbed LPC1768 using C without using a terminal emulator like minicom or teraterm?
For example if I send an integer from my C code than that led should be turned on.
How can I do this?
Without reading user manual or datasheet you can't do any thing to your board. So just go through it then follow below link for demo application LPC1768 board
1.NXP LPC1768 ARM Cortex-M3 Red Suite Demo
2.LPC1768 ARM Cortex-M3 CrossWorks Demo
3.mbed
4.At github
If you are using linux or osx check out the following answer:
How do I read data from serial port in Linux using C?
You can check your /dev folder and look for a file that is created when you plug your mBed. The file name would be something like /dev/ttyS0. That file represents the communication port, you can read/write that file to receive/send data over serial port.
If you want a cross platform solution try RxTx library for Java.
You can use this library
what it does, is that it initialize UART port which is connected to the debugger on your board and use it as serial input output. so with any hyper terminal of your choice, you can write code to do something if you send certain string of characters or just use original printf when something happens. and it will be printed on your PC screen.
I'm setting up i2c for an Application written in C, but I've not been able to find any how-to's for it. I'm running a model-b Raspberry Pi on Debian 6 with LXDE. Can anybody show me how to set up i2c so I can use it in a C Application?
Thanks for any help in advance
I've been looking for similar information and I found a couple of i2c tutorials, one in adafruit tutorials and the other in Guy Carpenter's Gaugette blog. I'm not yet at the stage of actually using it so I can't vouch for their completeness but they seem to be a good start.
Configuring Your Pi for I2C
Analog Gauges Using I²C on the Raspberry Pi
I2C Installation for Raspberry Pi. I think this is only necessary if not using AdaFruit's Occidentalis release which has it included.
try this :
C GPIO Interface library for the Raspberry Pi
It offers API for handling GPIO port on Raspberry, including dedicated functions for I2C interface. I've been using this to read measurements from temperature sensor and it works perfect (STCN75 connected to RPi rev. B).
You can find examples and instructions on author's website. Project is maintained and updated frequently on public Git repo.