Tstat10 General Communications Discussion

When I try to send a 1 line test program to the TStat 10, I get an error:

“Write Program Code Timeout!”

Any idea what I could be doing wrong?

Connected with COM1 port. Inputs/Outputs update.

Test Program
10 VAR20 = 20

Send (F2) generates error dialog box titled T3000 with error message and OK button.

I’ve tried slowing the BAUD rate down to 19.2K but that didn’t help.

I normally only run into this issue when I have communication problems. If the connection quality is low (green comm status at bottom of screen).
Are the controller inputs and outputs slow to modify or update when you are connected to the Stat?

Bret is correct, this sounds like you are not actually connected to the device. Use the status line down below showing the communications health. Jump around from inputs table to the outputs table and so on to generate some traffic and watch the RX and TX counts along with the error count.

I’m definitely having some type of communication problem with the Tstat10.

I have finally got a simple program to load; however, it is very unresponsive. The “Health” status at the bottom almost never shows 100%.

Several questions come to mind.

  • What version of the firmware is considered stable and works with WIFI? I’m currently using V62.7.

  • Is it ok to have both a wired connection and the WIFI enabled at the same time? Which method will it use?

  • Can the unit be programmed using WIFI connection, or is programming only supported with the serial connection? I have not been able to get programming to work with WIFI.

  • How frequently do updates occur to screens like input/output/variable? I have a simple program with a for/next loop incrementing a variable with a 1 sec delay. The variable screen shows the value changing maybe once every 10-60 secconds. Is this what is expected? If so why is it so slow?

  • Is there a setting that controls how frequently the Tstat10 is polled? If not what is the expected poll frequency if there is only 1 unit on the network?

  • Are modbus errors expected or should I expect to get almost 100% good communication. When I was talking to the Tstat10 with a python program using the modbus protocol, it would consistently get communication errors. Is this normal? The T3000 program seems to have the same issue. I have tried slowing the BAUD rate down to 19.2K, but that seems to have no affect. What is the recommended BAUD rate to use to get reliable communication?

  • I know I’m all over the map with questions, but I’m just trying to find some good starting point to try to develop around the device. If reliable and fast communication is not possible I’m wasting my time. Does anyone have the unit reliably communicating at a reasonable update frequency so the unit is usable in a network system with 100’s of devices?

Ok, I now have successfully disabled the serial connection and have been able to program the unit with WIFI.

I now see that if you switch to the Outputs screen and then wait until it has finished communicating at the bottom of the screen, you can then switch to the variable screen and that will trigger a poll which completes in about 2-3 seconds and updates the screen. If you switch back and forth between screens while it is communicating, the screens will not update. You must wait until one communication is complete before switching to another screen. There seems to be no button command or automatic refresh.

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Screen Updates: There is an auto update feature running in the background. The ‘values’ column gets automatically updated every 10 seconds. The entire grid also gets updated every 30 seconds or so. Also you can trigger a manual update of the values by clicking on the icons up at the top of T3000. If you are sseeing slow updates like 60 seconds then you should update T3000 and the device firmware too while you’re at it.

Multiple Connections: The devices can support simultaneous connections over RS485 and Wifi though you may see communications errors if there’s a lot of polling going on.

Versions: Its always best to run the latest firmware, you can see if there’s a new version by going to T3000 → help → check for updates.

Polling Settings: There’s no polling settings within T3000 but you can poll from your external master for example, as fast and often as you like. Youll start to see lost packets at some point, try adding a gap between packets to give the CPU some time to deal with its on board programs and other tasks. If you’re in Modbus use the block read commands to reduce the overhead. Our devices will respond quickly, too quickly in fact so you may need to add a delay to the modbus response, there’s a setting in the Tstat10 communications dialog.

Large Projects: We have clients managing hundreds of devices on a single twisted pair but in practical terms its best to break up large projects to subnets of 50 or so devices. This makes the system more robust and easier to debug when there’s problems.

In General: Keep in mind what is necessary to actually be polling. Temperatures and setpoints dont change all that often in the typical hvac system.

Need some help with the basics. T3-TB is connected via BACnet/IP.

I added a Tstat10 to the RS485main port. When I set up T3-TB and Tstat10 as BACnet MSTP then the Tstat10 appears in the T3000 screen as MSTPxxx (didn’t write it all down). I tried a second Tstat10 in Modbus Master/Slave mode and the Tstat10 appears in the T3000 screen, but I don’t see any Tstat objects appearing in BACNet.

What’s the right setting? Should both sides be in BACnet/MSTP mode? Is 115200 a good baud rate? And my understanding is MSTP MAC and Panel Numbers should be unique?

My goal is for a program in the T3-TB to control ports on the Tstat10. Feels like I’m close, but missing something simple.

Sorted out the problem. BIP Network settings need to match for everything to talk.

I’ve got the ConnectorIO Openhab BACnet binding talking to the T3-TB. Next step is to get it talking to the subnetwork devices on MSTP, but getting closer.

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Asher, I saw your posts there on Openhab.com. As I understand it their Bacnet support is in the early stages. If we need to do anything on our end just let us know and we will give this our full support.

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