To use busware SCC boards (see busware shop) with FHEM you have to:

1. Install FHEM (see my earlier blogpost)
2. If not already root

   $> sudo su -

3. Remove all reverences of the device ttyAMA0 (/dev/ttyAMA0) from /etc/inittab and /boot/cmdline.txt (if you use a Banana Pi you should look for ttyS2)
   

   $> nano /etc/inittab

   and replace

   #Spawn a getty on Raspberry Pi serial line
   T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100

   with

   #Spawn a getty on Raspberry Pi serial line
   #T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100

   and

   $> nano /boot/cmdline.txt

   and remove “console=ttyAMA0,115200” so that the file looks like that:

   dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait

4. On the busware hompage your told, that the boards occupie the following header-pins:
   • UART RXD
   • UART TXD
   • GPIO17
   • GPIO18

   The GPIO-pins 17 and 18 have to be pulled HIGH (17 for unreset, 18 could be untouched too). The best place to do that is in the fhem init-script that runs at startup.
   To do this, you have to open /etc/init.d/fhem  and insert the following lines inti the start-section of the launcher:

   echo "Resetting 868MHz extension module"
   if test ! -d /sys/class/gpio/gpio17; then echo 17 > /sys/class/gpio/export; fi
   if test ! -d /sys/class/gpio/gpio18; then echo 18 > /sys/class/gpio/export; fi
   echo out > /sys/class/gpio/gpio17/direction
   echo out > /sys/class/gpio/gpio18/direction
   echo 0 > /sys/class/gpio/gpio18/value
   echo 0 > /sys/class/gpio/gpio17/value
   sleep 1
   echo 1 > /sys/class/gpio/gpio17/value
   sleep 1
   echo 1 > /sys/class/gpio/gpio18/value

    

5. Reboot the system:

   $> reboot

Further readings:

• http://shop.busware.de/product_info.php/products_id/97
• http://busware.de/tiki-index.php?page=SCC
• http://busware.de/tiki-index.php?page=SCC_Installation