I am glad you found the problem. Good to hear that your system runs now.
Iâ€™m sorry, but we cannot reproduce your problem.
Could you please provide us with a step-for-step instruction, what you do, starting with the download of the newest kernel sources. Please also use the newest toolchain (4.7.2) and the provided binaries of the uboot and rootfs.
Best regards, Micha
I tried your program with a new Kernel V1.4 and the patch above and it worked.
All steps I did: I downloaded and installed the newest available Kernel source (V1.4) and the newest toolchain (4.7.2). The above patch was applied in the kernel root path (e.g. ~/linux/linux-2.6.38-f+s-V1.4/). Then I built the kernel with make picocom4_defconfig and make.
After downloading and starting the kernel on the PicoCOM4, I remounted the rootfilesystem (mount -o remount,rw /) and created a new user telnet (adduser -D telnet) with no password (passwd -d telnet). The telnet client needs to be started on booting. So the file /etc/S70telnetd was created with the following lines:
In the file /etc/inittab I commented the login_tty configuration and removed the console in the uboot. To do this I viewed my enviroment variables with printenv bootargs and then copied everything from bootargs. The content of the bootargs variables is listed below.
Then I rebooted the board, logged in via telnet and started your test program. After those steps a serial connection with 115200 baudrate showed â€œTestmessageâ€. It also worked with ttySAC0.
After there were questions about how to do a SD Card Connection with a specific pin, enclosed you can find an example project using the digitalio driver to connect the SD Card if an interrupt on the pin occurred.