Communication with DX9100 through the N2 BUS

[LauPro]

I've a DX9100 with a XT and a N2 bus. With a RS232-RS485 converter i can 'watch' the traffic on the XT-bus, this works great. It is posible to read the values from every device.

But now i want to read directly the N2 bus from the DX9100. I've set my converter in 'half duplex multidrop mode' and the DX9100 on address 1. When i send the following message:

>01FA7cr (cr is actually \r or character 13)

But i don't receive anything on the bus. I've tested it on 2 DX9100's now. Does the DX9100 need some extra configuration with the GX9100 tools? (M-tools) I don't have those tools atm.

What can i do to make the communication work?

[s2sam]

I've a DX9100 with a XT and a N2 bus. With a RS232-RS485 converter i can 'watch' the traffic on the XT-bus, this works great. It is posible to read the values from every device.

But now i want to read directly the N2 bus from the DX9100. I've set my converter in 'half duplex multidrop mode' and the DX9100 on address 1. When i send the following message:

>01FA7cr (cr is actually \r or character 13)

But i don't receive anything on the bus. I've tested it on 2 DX9100's now. Does the DX9100 need some extra configuration with the GX9100 tools? (M-tools) I don't have those tools atm.

What can i do to make the communication work?

Good day,

Although the DX can be connected to the N2 bus, it does not communicate using the N2 protocol... which is why you do not get a response from the DX. The DX uses an entirely different protocol than N2-Open for communication. Both of these protocols can co-exist on the same bus, but their format is dramatically different.

The differences also extend to how the point information is seen. The N2 protocol abstracts the point information using objects, but the DX expresses its point information through memory location(s)...

In response to your question... to communicate with a DX you require the DX protocol, which to knowledge JCI does not currently disclose. JCI may have changed their policy on this and so it may be worth a try to contact them to obtain it.

Cheers,

Sam

[krac]

But now i want to read directly the N2 bus from the DX9100.

Does the DX9100 need some extra configuration with the GX9100 tools? (M-tools) I don't have those tools atm.

What can i do to make the communication work?

Don't waste your time trying to reverse engineer an obsolete protocol. At one time JCI used to send on request, a copy of all the protocols, but now they just ship the N2Open specs. The DX9100 N2 protocol is a complex mess compared to the more simplistic ASC N2 protocol.

To do anything with the DX you will need a copy of the GX9100 configuration and commissioning programs to get the controller setup.

[LauPro]

Hmm, i've the item lists for the memory addresses and stuff. But only some documentation about the N2 protocol which only let me understand the basics.

So the target is now to find the software and fix it.

[orion242]

I would be interested in the DX protocol if anyone is willing to send a copy my way.

Email is in my profile.

[steves4]

It sounds like you were trying to access other devices on the N2 bus from a DX-9100. To the best of my knowledge the DX-9100 cannot act as a bus master on the N2 bus as do the Metasys supervisory controllers. The DX-9100is always a slave device on the N2 bus.

Take a look at www.thes4group.com if you are interested in solutions to communicate with devices on the N2 bus. Our S4 Open products provide open protocol interfaces to any device on the N2 bus. This includes the expansion modules on a DX9100 XT bus. Please contact me directly if you would like additional details.



I've a DX9100 with a XT and a N2 bus. With a RS232-RS485 converter i can 'watch' the traffic on the XT-bus, this works great. It is posible to read the values from every device.

But now i want to read directly the N2 bus from the DX9100. I've set my converter in 'half duplex multidrop mode' and the DX9100 on address 1. When i send the following message:

>01FA7cr (cr is actually \r or character 13)

But i don't receive anything on the bus. I've tested it on 2 DX9100's now. Does the DX9100 need some extra configuration with the GX9100 tools? (M-tools) I don't have those tools atm.

What can i do to make the communication work?