Hi Gorden,
first i also have to thank you for your great work. Is there a possibility to define the port more specific (i need a parity bit 🙁 )

Hi Gordon. I tried a simple program but it is not as expected. I connected the RX and TX header together just for testing this program:

int fid = serialOpen(“/dev/ttyAMA0”,9600);
serialPutchar(fid, ‘k’);
printf(“%d\n”,serialGetchar(fid));

But the outcome is always -1. Help?

hi
when i call serialGetchar it allways waits 10s and return -1 another functions works
i can send data from /dev/ttyAMA0 to my serial terminal but it don’t recieve any byte
i am sending it with 1 stop bit 8 bits and no parity
i just call your function and write result on display

Hi Gordon,

Hi Gordon.,

I installed library and copied the first examples with the GPIO. Works great!
I have now tried anzusprechne UART and without success

I compile with the
g++ name.c -o name -l wiringPi

try to do with sudo ./name

Tx and Rx are crossed

Code is

#include
#include
#include

//#include
//#include
#include

int main (void)
{
printf (“Raspberry Pi wiringPi Serial test program\n”) ;

char * Device;
sprintf(Device,”/dev/ttyUSB0″);
int fd = serialOpen(Device, 9600);
if (fd < 0)
{
printf ("Unable to open serial device: %s\n") ;
}
else printf ("serial device is open\n");

serialPutchar(fd, '1');
printf("%d\n",serialGetchar(fd));
serialClose(fd);
return 0 ;
}

Please help!

do you have a some examples as Code?

Thanks a lot

Hi ive been looking at serialRead.c.

and i have noticed a function(?) i am not familiar with fflush().

From watching your code execute i can see that the code is reading the serial port and outputting the character to the (stdout) in this case the terminal client.

my question is how would i take the input from the serial port and output it to a bit in an Array

i have tried

putchar (serialGetchar (fd)) ;
fflush (F[1]) ;

but i must be missunderstanding the fflush function. thanks

Hi Gordon
I have a big problem. I must use the function serialPuts to send an hexadecimal string that can have the number 0 within. In this case doesn’t send the entire string but send the character until the null char.
how can i do?

thanks

Hi, there? Thank you for your library.
But I got the problem. When I use the “serialRead.c” first some times good, but later, randomly serial connection be crazy! 🙁
Pi gives me “ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ” What happen?

And i can’t send data. On “serialTest.c”, serialPutchar() and serialPuts() are doesn’t work. How do i solve??

Gordon,

Thanks so much for your great Raspi support. I’m using all aspects (wiringPi, I2C, and serial).

I have a question: I’m trying to drive a serial 20×2 LCD. I can send std ASCII characters fine, but need to send various ‘control characters’ such as 0xFE in order to clear the display, move cursors and such, but when I send something other than ASCII, the char gets echoed to stdout and it does not seem to get sent over serial. I have already interfaced to the same LCD using Arduino with no problem.

Any ideas? Thanks again…

Hi Gordon,

I have installed your latest version and have attempted to run your serialTest program. I get absolutely no output from the console. After some debugging I have found that it never finishes opening the serial port. It halts on the first if statement if I do not run with sudo, but I do use sudo, it never passes the if statement. I’m stumped, any ideas what could be wrong?

Thank you

Hey Gordon ,,

I have a dimmer light that controlled by serial data for example by using UART pin from the Raspberry pi to send 8 bits for each command

I need a way to know how to send (00000001) and any 8 bits pettern out of the TxD ?

Thank you 🙂

Forgot! Thanks a lot for the lib! The other modules work great!

Hello Gordon,

I use the library “wiringSerial” for communicate with a GPS module by the Uart GPIO port.

I have done disable the serial consol and i do:

if(fd = serialOpen(“/dev/ttyAMA0”, 4800) < 0) // Configure the Serial port
printf ("\nUnable to open serial device \n");
else
{
printf ("\nUnable to open serial device \n");
}

Hi,

I’m seeing some strange behaviour with serialTest that maybe someone can help me with? I ran the example code and nothing was happening, it just froze, so I added some debugging lines and the strange thing is they only appear if I run the program without using sudo. I’ve tried to break the problem down as much as possible, so if you look at my below code, running ./test will print the line 0, and then fail to connect to the serial port, whereas running sudo ./test won’t even print the debug “0”. I’ve had this working previously, and so I thought maybe I’d blown the serial port up (connecting to my arduino), so I’ve bought a new pi and it’s still doing the same.

#include
#include
#include

#include

int main()
{
printf(“0”);

int fd;

if((fd=serialOpen(“/dev/ttyAMA0”, 115200))<0)
{
fprintf(stderr, "Unable to open serial device: %s\n", strerror(errno));
return 1;
}

serialPutchar(fd, 'i');

return 0;
}

Hi!
I have the following c:

#include
#include
#include

#include

int main ()
{
int fd ;

if ((fd = serialOpen (“/dev/ttyUSB0”, 9600)) < 0)
{
fprintf (stderr, "Unable to open serial device: %s\n", strerror (errno)) ;
return 1 ;
}

// Loop, getting and printing characters

for (;;)
{
printf("–%x", serialGetchar (fd)) ;
fflush (stdout) ;
}
}

except the correct data "–96" i also receive "–ffffffff".
What is going wrong?
Thank you!

hi… Gordon sir, I am trying to send and receive the data serially by using on board tx and rx pins i,e., 8 and 10. but i am getting error in serialOpen() function.
My code is
int dt;
char p[]={“/dev/ttyAMA0”};
char *device = p;
dt = serialOpen(*device, 9600);

the error is: bad assress
please tell me how give address in device pointer.

Thanks in advace

sir, i am sending “44” from xbee but it gets 10 after hits enter or 32 after press space and enter.

Dear Gordon,
first I’d like to thank you so much for your great libraries!
Your GPIO lib work without any problem so far.
Yesterday I tried to work with your serial lib, with the first attempt I could receive char’s at my PC, only receiving with the RPi won’t work, but this I’ve planed to checkout this morning. After a shut down of the RPi (last evening), I tried to start my app this morning (code unchanged), but unfortunately, when serialOpen is called:
nHandle = serialOpen(“/dev/ttyAMA0”, 9600 );
The function doesn’t return, but the day before it did! I assume, may be I have done any shell cmd on the RPi, which made it work yesterday, but I don’t remember.. I’ve really got no idea?

Calling the regular open() function, it always returns a valid handle, but transmitting of char won’t work, as well!

nHandle = open(“/dev/ttyAMA0”, O_RDWR | O_NOCTTY | O_NDELAY);

May be you have an idea or hint for me?

Regards and thanks in advance!
Ralph

How can I read the input to a variable and then write it to a file. I have tried a few ways but it seems to just print strange characters to the file. It prints to terminal fine but I am unsure how to get the input into a variable. The text I am sending from my arduino are two letters long. Let me know if you need any more details about it.
Thanks in advance.