I’d first recommend you flash your Edison with the latest image. If you type configure_edison and get an error message like “command doesn’t exist” may lead to other problems. Besides, if you flash with the latest image it will be easier to troubleshoot issues like this. To flash with the latest image go to IoT - Intel® Edison Board Download | Intel® Developer Zone and download the latest image and the Flash Tool Lite. After doing this and installing the Flash Tool Lite, follow this guide to flash IoT - Flash Tool Lite User Manual | Intel® Developer Zone .
At this point you should see 159 as the output for “configure_edison --version”.
To check the status of any serial port on the Edison you can use dmesg | grep tty###
You can see the serial ports on the Edison in this link Using Serialx on Edison
thank you very much for the fast reply.
I flashed my edison with the newest version of yocto (output of configure_edison --version is 159).
I have downloaded and installed mraa lib using instruction from this githab Readme
Than, created (sent to) a file named "hallo_mraa.c" to the Edison, with the content of the example you recommended
(adding printf messages if the command if (uart == NULL) returns false - which means it configured the UART - let me know if I'm wrong ).
After that, compiled it with :
gcc hallo_mraa.c -o mraa -lmraa
which returned nothing to screen (compiled successfully as far as I understand).
than, I connected the USB cable to my PC (wired same as at first comment: grd->grd, rx->tx, tx->rx), found ttyUSB0 to be the name of the port, and opened serial connection listening to it (at my PC):
screen /dev/ttyUSB0 115200
when I run the program mraa I've compiled before, it print to screen the added printf ("UART successful\n"), but, didn’t get nothing at USB0's terminal.
(I didn't configure the pins multiplexing like at the first commant, I guessed it is done by uart = mraa_uart_init(0); ).
the outpu of dmesg | grep ttyMFD1 is
[ 0.708859] 0000:00:04.2: ttyMFD1 at MMIO 0xff010100 (irq = 29) is a hsu_uart1_port_p
no matter if the CP2102 converter if wired or not.
I would like to get some directions for checking what is wrong and how can I make it work.
Thank you very much
We tested the code you are using and got the string “Hello Mraa!” into the port /dev/ttyMFD1 which is UART1 (Pin 0 and 1).
After you run the compile command, gcc created the executable file correctly?
What is the name of your .c file?
To compile a C file named hello, for example you’d have to type
gcc hello.c -o output ./output
Does this part runs correctly without errors?