Forum posts to 'General Discussions'

problem with beagle board serial port

vishal gosai — Thu, 26 Jan 2012 05:35:28 +0100

problem with serial port

I am currently working with the beagle board in which Linux is ported. I have written program in it so that It continuously reads the data coming to the serial port.I send the requests(at every 1 second) to it by modbus tester(In another PC) but when it reads the requests, immediately it(beagleboard) sends the garbage bytes to the serial port.I don't write to the serial port or nothing at all do to write anything to the serial port(in beagle board) still it writes immediately after reading the requests.
I have attached a piece of code at beagle board side..(assuming all necessary declaration)

int main()
{
int num_read,i,j,l;
char read_buffer[11];
char *nums_read = &read_buffer;
char nums[] = {0x02,0x04,0x00,0x00,0x00,0x02,0x71,0xf8};
char *nums_write = &nums;

serial_port_open();

while(1)
{

signal (SIGINT, (void*)sigint_handler);

tcflush(serial_port,TCIOFLUSH);

// The main program loop:

for(l=0;l<10;l++)
{ for(i=0;i<65535;i++)
{

if (serial_port != -1)
{

num_read = serial_port_read(nums_read, 9);

if (num_read > 0)
{
goto pa;
}

}

}
}
pa:j=1;

}
}

int serial_port_open(void)
{
struct termios options;

serial_port = open(PORT_NAME, O_RDWR | O_NONBLOCK);

if (serial_port != -1)
{
printf("Serial Port open\n");
tcgetattr(serial_port,&options_original);
tcgetattr(serial_port, &options);
cfsetispeed(&options, B9600);
cfsetospeed(&options, B9600);
options.c_cflag |= (CLOCAL | CREAD);
options.c_lflag |= ICANON;
tcsetattr(serial_port, TCSANOW, &options);
}
else
printf("Unable to open /dev/ttyS2\n");
return (serial_port);
}

int serial_port_read(char *nums_read, size_t max_chars_to_read)
{
int i,l;

int chars_read = read(serial_port, nums_read, max_chars_to_read);

usleep(20000);
tcflush(serial_port,TCIOFLUSH);

return chars_read;
}

A part of the observation of free serial monitor is written here.Request is issued by the modbus tester and answer(undesired) is given by beagleboard.I don't know how it writes into the serial port...please help me work out this problem as soon as possible...

Request:
01 01 00 00 00 64 3D E1 01 01 00 00 00 64 3D E1 01 01 00 00 00 64 3D E1

Answer:
5E 41

Request:
01 01 00 00 00 64 3D E1 01 01 00 00 00 64 3D E1 01 01 00 00 00 64 3D E1 01 01 00 00 00 64 3D E1

Answer:
5E 41

Request:
01 01 00 00 00 64 3D E1

Answer:
5E 41

..........

Posted to: problem with beagle board serial port

Re: Is this site still up to date?

Kerstin Balka — Tue, 03 Jan 2012 12:56:21 +0100

Activity has been a little lower recently. However the list is still mostly up to date. If you are missing anything or if things have changed, feel free to update ;-)

Cheers
Kerba

Posted to: Is this site still up to date?

Is this site still up to date?

bram geenen — Mon, 02 Jan 2012 12:27:30 +0100

I was wondering if this list of open projects is still up to date? It looks like there is little activity on the website.
Is there another website that keeps a list of open projects?

Posted to: Is this site still up to date?

Re: Is posting our project on this site sufficient...

Kerstin Balka — Sun, 18 Dec 2011 15:06:45 +0100

Depends on how you define Open Source...

If you want your project to be Open Source from a legal perspective, you should use an open license, e.g., through Creative Commons. Thereby you can also protect it from being used in closed source context by someone else, if you want to.

Independent of the legal perspective, I would define a project as Open Source, as soon as you share knowledge and/or allow contributions by others. In this regard posting it on this site is a first step, but not sufficient, as you cannot reveal specific knowledge here.

Cheers
Kerba

Posted to: Is posting our project on this site sufficient...

Re: Is posting our project on this site sufficient...

Fred Frazelle — Thu, 13 Oct 2011 20:49:51 +0200

How interesting... 2,800 views and no reply. Hmmm...

Have a great morning! :)

Posted to: Is posting our project on this site sufficient...

Is posting our project on this site sufficient...

Fred Frazelle — Wed, 14 Sep 2011 21:48:38 +0200

to insure that it falls under OpenSource? We have started a project here called SolarProjects and our first one has to do with concentrated solar hot water and we wish it to be OpenSource. However obviously not all components are OS - such as the tracker circuit, the dome for the tracker circuit, etc.

So, would posting what we have done on this site be sufficient to allow whatever knowledge we have been able to add to this topic/product to be of the OS type?

Have a great afternoon! :)

Posted to: Is posting our project on this site sufficient...

Re: Why do you participate in OS projects?

Sunny Forsyth — Sat, 29 May 2010 09:37:52 +0200

Hi Kerstin,

Great question! For me it was the only feasible way for myself and a small group of people to do a project such as this. We are designing a very simple water filter but more than that we are implementing it in villages on the ground in SE Asia. There is too much work for a few people to do by themselves and there are lots of people really excited by our project but they are in other countries. Open source offered a natural solution to allow people from around the World to contribute to the project. Our project can be found at http://abundantwater.org if you are curious.

Cheers,

Sunny

Posted to: Why do you participate in OS projects?

Which platform do you like the best?

Janani GV — Wed, 24 Mar 2010 07:21:34 +0100

Hi!

I'm a freelance writer based in India, and do a lot of writing on open source software and hardware, for Electronics For You as well as for Linux For You (and linuxforu.com).

As my next project, I'm trying to check the community's preferences regarding open source hardware platforms. There are many available these days... beagleboard, arduino, gumstix, OpenRISC, and so on. Which has gained the most traction and why?

Would be great if you could take time to share your views on the following points...

a) Which open source hardware platform do you like the most? Why?

b) Does the platform you've chosen adhere to all the rules of being truly 'open source'?

c) What are the three largest technological highlights of the platform you've chosen... that is, how does it excel technologically compared to the other options?

d) How is the community spirit surrounding this platform? That is, why do you like being part of the project's community?

Useful and insightful responses will be published with the story... so please share your name, designation (or short bio) and a photo, if possible by email.

Look forward to hearing from you all :-)

Regards,
Janani
gjanani@gmail.com

Posted to: Which platform do you like the best?

Re: "Open Innovations Project"

Kerstin Balka — Wed, 04 Mar 2009 18:09:27 +0100

Uhh, some time has passed and we still did not decide for a new name. I like the term "open design" as well, it describes our intent more precisely then open innovation or open source innovation.

However I'm still struggling with the length of the name. Opendesignprojects, opendesigninnovations, and similar are not the shortest urls and I like short urls that people can remember ;-)

So if anyone has another good suggestions, you're very welcome to post more ideas. Rather sooner than later we should anyway come to a decision...

Cheers
Kerba

Posted to: "Open Innovations Project"

Re: Why do you participate in OS projects?

Martin Brüggemann — Sat, 24 Jan 2009 19:14:44 +0100

Hi Kerstin,

good question!
Through hard and sometimes frustrating experience (not so much @ university, more in various jobs) I have come to the conclusion, that innovation has a...well...inferior standing.

What you always have are worriers, you know?

What is zillions of times easier to achieve are small incremental improvements, which you get for free by a community:
In my area of business, that means correcting a typo here, finding a better formulation there, getting a better graphic from another project.

If you understand what I mean, you can keep it ;-)

Posted to: Why do you participate in OS projects?