Thank you Christof and Martin for your advice. I am using a powered hub and am powering the components being controlled by the arduinos separately. Now I think the whole system is overheating because when I open the enclosure it seems to work much better. I am going to try a few small fans and see if that helps now. I also now have access to a mac mini with more usb ports so I might try that as well. Eventually I'd like to port it all over to a group of rpis -maybe even 1 for each arduino. Thanks again.

Cheers,

Rick

On Tue, Aug 30, 2016 at 10:31 AM, Martin Peach <chakekatzil@gmail.com> wrote:

On Mon, Aug 29, 2016 at 10:55 PM, Rick Snow <ricksnow@gmail.com> wrote:
Howdy list,

I am using comport to send messages to three arduinos via osx for an installation. Almost invariably one of the connections drops after an extended period of time. It seems that only unplugging and replugging in the usb hub's usb cable will refresh the connection (after sending the connect message again from the patch). I am running the project on an older macbook pro with osx 10.8.5. Is this a usb hub problem (radioshack brand) or should I be looking at something else?

Most laptops don't have a lot of juice in the USB connector so you should power the hub separately (although some (e..g. thinkpads) have one USB socket that has more power capability). Also if the arduinos are running servos or anything that takes a lot of power they should be on their own power supply (not USB).

Martin