19 CP4a on AXLink

No problem.

jwells wrote:

Hi,
I'm planning a system which will have 19 CP4 touch screen contolling a residential property from a single NI-4000. I'm a bit concerned about the number of panels on the AXLink bus. Has anyone had this many CP4's on a singel AXLink bus or am I just asking for comunication problems ?

Cheers
Justin

The only limitation to the AXLink bus is that the total cable length of all legs must not exceed 3000 feet.

I have a system working perfectly with over 150 AXLink devices including 15 10.4" touch panels each configured as 4 devices. This system uses an NXC-ME/SPE with an AXLink server port expander.

jwells wrote:

My main concern was the communications speed of AXLink only being about 20.8Kbps and the fact we will be using a Music server which these panels will be requesting information from and possibly cover art (if it can). I thought about adding a separate NI-700 processor and equally splitting the panels between the two controllers, but I guess this could be my backup plan.

Thanks

Sending text to buttons on a CP4 via Axlink is somewhat slower as compared to a Modero on Ethernet. Since the panel is small I doubt if you will be updating more than 6 lines at a time which should be fine.

Splitting the system between two masters will not provide a significant difference in performance and would overly complicate the programming.

The system I described above was running fine on an Axcess master for many years before converting to NetLinx. Populating multiple text fields was handled with while loops to increase performance. You won't have this problem with NetLinx.

There is no way to display cover art on a CP4.

GSLogic wrote:

Justin,
My advise is to only send text/button info to panels that needs to see the changes, loops... loops and more loops. It's alot more work but will keep the system running clean.

Great advise, Gary.