The Pi is full speed only splitted. That explains why I have trouble using the OTGW and the serial cable to my Inverter at the same time.pwhooftman wrote:I used the cheapest USB I could find at home and it seems that it is working now. Domoticz hasn't crashed yet and the data from the OTGW keeps updating.Deshke wrote:Note that the OTGW only supports full-speed serial interfacing via the USb interface. If the Raspberry has a high speed USB interface, this will likely cause issues similar to your findings (it seems to work, but only for a limited time (minutes to hours). Same happens when using an TP-Link WR703N router to make the OTGW LAN/Wireless accisble. Solution is to put an inexpensive USB hub in between the OTGW and WR703N. Dont know is the same problem applies to a Raspberry. (reference: http://www.domoticz.com/forum/viewtopic ... &start=180 )
According to the RPi website.GENERAL LIMITATIONS
The OTG hardware on Raspberry Pi has a simpler level of support for certain devices, which may present a higher software processing overhead. The Raspberry Pi also has only one root USB port: all traffic from all connected devices is funnelled down this bus, which operates at a maximum speed of 480mbps.
The USB specification defines three device speeds - Low, Full and High. Most mice and keyboards are Low-speed, most USB sound devices are Full-speed and most video devices (webcams or video capture) are High-speed.
Generally, there are no issues with connecting multiple High-speed USB devices to a Pi.
The software overhead incurred when talking to Low- and Full-speed devices means that there are soft limitations on the number of simultaneously active Low- and Full-speed devices. Small numbers of these types of devices connected to a Pi will cause no issues.
I only do not completely understand why the cheap hub solution works....