DC board power-up procedure

[Nixay]

Hi, just wondering what the official procedure for powering-up and down a DC board is. Is it power-up the DC board's power supply, then connect the USB or vica versa?

I'm just testing LEDs with a single DC board at the moment running at 12v but I'm having all sorts of problems with the LOR II Hardware program crashing when I turn off the DC PSU with it still attached to the PC, and then on restart telling me there's a problem with the port, then the port is in use etc.

I've just been trying different combinations of DC PSU power on, connecting USB converter with network attached, or just USB on it's own without the network attached until it works. Haven't really found a reliable method of powering-up and then powering-down yet without a crash. This concerns me a bit because my plan come december will be to have the control PC on 24/7 but the PSUs running the DC boards will be on timers to switch off during the day (it's summer in Australia, gets quite hot during the day and don't want to leave them running).

Any clues would be great, and sorry if this is covered elsewhere already.

Andrew.

[-klb-]

I don't think the issues you are having relate to the DC board power up/down sequence. To me it sounds more like either an issue with the drivers for your USB adapter, or maybe something with the hardware utility install on your PC.

I am not terribly surprised if when the HW utility crashes, you may have to reboot the PC before any of the LOR programs will work against the serial port again. The reason being that only one program is allowed to talk to a serial port at a time, and if windows was never notified that the port was released, and it fails to realize that the program that had the port has died, Windows will never let anything else attach..

However, in December, you probably won't be running the hardware utility much, if at all. Shows are run from the LOR control panel, and you can not have the control panel and the hardware utility active at the same time... I never have had issues with controllers being power cycled having any impact on the control panel or HW utility. You probably want to check on your system that the control panel app is stable through controllers being cycled up and down. You should be able to have the control panel up, and enabled, and playing a show, and still be able to shut down and start up the controller without causing any problems...

If you have problems with this, the two things I would check are the USB drivers, and that your USB adapter is fully recognized when it is plugged into the PC without the controller.. I could see possible cases where the USB-485B might itself be powered from the DC controller, in which case it could shut down when the controller is turned off, and cause all sorts of fun..

- Kevin

[Nixay]

Interesting. I'll have a play around with the different components of the software and see what I come up with. Honestly I've spent so much time on the hardware side with these LEDs I haven't tested much with the software!

I am using a USB-485B converter. I think I have actually noticed that the status LED on the board starts blinking when it's connected to the USB, but no DC power applied. Then after DC power is applied it stays blinking (obviously) but after the DC power is removed and while still connected to the USB the status LED goes out - I thought that was weird. Like it's getting power initially from the USB, then falls over to the DC supply when that's turned on, but then doesn't fall back to USB power when DC is removed.

I'll play around. I just bought this second-hand PC to be my control PC and I wouldn't be surprised if one or two of the USB ports have issues (only about 4 years old though).

Andrew.

[-klb-]

Nixay wrote:

I am using a USB-485B converter. I think I have actually noticed that the status LED on the board starts blinking when it's connected to the USB, but no DC power applied. Then after DC power is applied it stays blinking (obviously) but after the DC power is removed and while still connected to the USB the status LED goes out - I thought that was weird. Like it's getting power initially from the USB, then falls over to the DC supply when that's turned on, but then doesn't fall back to USB power when DC is removed.

I agree that this is odd. The USB-485B should power a single card's logic just fine, both before and after DC power is applied. However, I can see where if the USB drivers crashed, or for some other reason Windows decided that the USB-485B was no longer active, it could shut down power to the USB port, and in turn the DC card..

- Kevin

[Nixay]

Ok, I've done some more experimentation with this. The problems definitely start when the DC power is removed and the LED status light goes out, indicating no power to the controller anymore and presumably the USB485B as well.

Here was my test procedure on my show PC, simulating what I'll be doing in December. This test involved a DC controller with single regulated 12V supply connected in parallel to both banks on the card with no additional supply connected to the auxillary power input, and LED lights on 15 of the 16 channels, connected to a USB485B via a short (1m) CAT5 cable, and then the supplied USB cable.

- Connected USB to USB485B adapter and status LED on DC board started blinking
- Applied DC power
- Opened Hardware Utility, scanned for devices, status LED solid, and turned lights on and off.
- Closed Hardware Utility, status LED blinking
- Removed DC power

At this point the status LED stayed blinking, so all appeared well and I did the test again successfully. But on my third attempt:

- Applied DC power, status LED still blinking
- Opened Hardware Utility, scanned for devices, status LED solid, and turned lights on and off.
- Closed Hardware Utility, status LED blinking
- Removed DC power, STATUS LED WENT OUT.

Then:

- Applied DC power, STATUS LED CAME BACK ON AND BLINKING
- Opened Hardware Utility and got the following error:

The serial port (Comm3) assigned to LOR has a problem.
You may need to select another port.

Internal error retrieving device control block for the port
Trace: PollStation

At this point Comm port 3 is unusable until it is physically removed from the USB port and then reconnected. I then tried the other 3 USB ports on the PC in turn and basically returned the same intermittent results, but then eventually got all tied up in knots and wouldn't work at all (reboot). I have tried this test on my main PC as well and it's rock solid with no problems (it's assigned to Comm7 if that makes a difference).

My only guess at this point is perhaps my show PC isn't supplying enough power to the USB ports to maintain power to the USB485B adapter. I noted that after the status LED went off, when DC power was reapplied to the controller, this didn't rectify the problem and perhaps the USB485B doesn't receive power back from the controller, it may rely solely on the USB power which appeared to have failed at this point.

If my guess is correct perhaps a powered USB hub would help, although surely this isn't pulling any more than 500mA (USB limit, correct?). Anyone else experienced this?

Andrew.

[Nixay]

I have since done this testing again using actual scheduled test shows instead of just the hardware utility and the problem still occurs.

However I think http://lightorama.mywowbb.com/forum71/15518.html is describing the same problem - looking like a USB driver issue with the USB485B. Didn't see it over there in the LOR I section cos I'm using LOR II........

[-klb-]

I almost wonder if your issue might not be related to differences in the ground potential, since it is so repeatable when you turn off your DC power supply...

Though it is not available yet, I wonder if the isolated USB-485 adapter referenced here would help:

http://lightorama.mywowbb.com/view_topic.php?id=16635&forum_id=76&highlight=isolated

Difficult to say for sure now...

- Kevin