/dev/ttyAMA0 disconnected, waiting to reappear (SCC_0)

[fhemmiv]

Hi all,

I have a setup with a RPi an SCC from busware and some MAX! devices. I recently moved from using a usb CULv3 to the SCC extension board.

The CULv3 setup was running without problems but when I moved to using the SCC device I saw the following problems reported into the FHEM log and all communication with the SCC stopped and in fact all my central heating stopped working.

2014.11.23 16:23:52 1: CUL_MAX_Parse: len mismatch
2014.11.23 16:23:55 1: /dev/ttyAMA0 disconnected, waiting to reappear (SCC_0)
2014.11.23 16:23:55 1: Error in CUL_MAX_SendQueueHandler: CUL SCC_0 did not answer request for current credits. Waiting 5 seconds.
2014.11.23 16:23:57 1: Error in CUL_MAX_SendQueueHandler: CUL SCC_0 did not answer request for current credits. Waiting 5 seconds.

To get it to work again I have to stop and restart fhem and all is fine. I do not have to reset the SCC. The only thing is that I have the following extra lines added to my fhem startup script.

# Prepare GPIO-17 for SCC (CUL) extension board
if test ! -d /sys/class/gpio/gpio17; then echo 17 > /sys/class/gpio/export; fi
echo out > /sys/class/gpio/gpio17/direction
echo 1 > /sys/class/gpio/gpio17/value

I have had this problem now three times in the last four days. The last time it happened in the middle of the night so now I have installaed a monitoring agent (Zabbix) on it which restarts fhem automatically when it detects the error in the fhem log.

The culfw on the SCC if the stock one deliverd by busware version 1.61. For fhem I am using the svn nightly version from  november 9th.

To me it looks like not all data is read from the SCC "CUL_MAX_Parse: len mismatch" by which the device is disconnected "/dev/ttyAMA0 disconnected, waiting to reappear (SCC_0)". But as this is not a usb device it will not reappears so fhem never creates a new connection to the device.

Anyone seen this before?
All help is appreciated. I do not want to go back to the CULv3 usb device as I need it for other things.

Regards,
Michel.