Mitsubishi Television RS-232 woes

kmkorf

Hey folks,

I've been beating my head today to get a Mitsubishi WL-82913 to respond to serial control commands. I have verified all my code and have even connected directly to the TV with my PC. I have verified the wiring and that the TX and RX lines are crossed appropriately with a test device. It appears the the serial lines are getting power from the TV. Connection wise, everything looks good. When I send a string to the TV, I get no response at all, not even any error messages. It didn't matter weather it was the NI-4000 or my PC that was issuing the commands.

We do not normally sell Mitsubishi TVs (but we have used their projectors with no issues) so I was hoping I've just overlooked something in the garbled menus in the TV. It seems to just be ignoring all communications from the serial ports.

I have a call into Mitsubishi that has been escalated to their second tier support but I have to wait 1-2 business days from the day following my call before they call me back. Given I called them today, my 1-2 day waiting peroid will start from Monday so I won't get any info from them until at least Tuesday or Wednesday next week. Hopefully someone has faced this before and can respond quicker than Mitsubishi.

Thanks,
Kurt Korfhage
Simplified Technologies

Thomas Hayes

Have you tried changing the baud rate around? Is it the normal 8N1 or something else.

kmkorf

I used my trusty terminal emulator and stepped thru all the different baud rates with no luck. The TV is supposed to be 9600, Odd parity, 8,1.

Thomas Hayes

Do you have a PDF of the manual?

kmkorf

Here's the PDF all Zipped up that contains the RS-232 protocol. There are a few typos I've found but for the most part it is accurate. I got it under the "Technical" section of their website:
http://www.mitsubishi-tv.com

Thomas Hayes

Hi Kurt
The codes are pretty straight forward, doesn't appear to be anything to odd. I just read the manual and ditto for it also. They say that the monitor/rs-232 connector is auto-detecting between the two, is there anywhere in the OSD that allows it to be forced?

kmkorf

If there is a way to force its behavior, i haven't found it. And the menus on the TV are the least intutive I think I have ever encountered.

frthomas

Re: Mitsubishi Television RS-232 woes

Originally posted by kmkorf
It appears the the serial lines are getting power from the TV.

Huh, that's strange. You mean you get 12V between either Rx or Tx and GND? If you do, then there is no wonder it does not work, as obviously the voltage difference is used by the serial port hardware to detect data going though. (sorry if this is obvious, just trying to help).

Have you checked your cable between with another devices? It could be shortcutted some place (again, obvious but it is so often the cable...)

Otherwise same comment as the other, except for the ODD parity, there's nothing that special in the protocol.

Hope this helped

Fred

Thomas Hayes

Is the 12V to power their ' box ' that can also be plugged into this connector? Does pins 2,3,5 of your connector match the TV's pins 2,3,5: The reason I'm asking is awhile back I had a shipment of d-conn's come in that the pins were labeled wrong. Talk about hard to troubleshoot a problem like that.

kmkorf

Let me clarify on how I have verified that the cable is good and the TX and RX lines are properly connected. We have a small, passive, inline serial tester called the Quick Tester. It has indicator lights that are powered by leaching the voltage on the serial TX and RX lines (which I think is around 5V, not 12V). It also has switches so that it can be configured to cross the lines for TX/RX, DRS/DTR, RTS/CTS/DCD. This tool has never failed me when trying to get the wiring right. (I've included pictures of the device in action for your viewing pleasure). When both the Red lights are illuminated that indicates that TX and RX are aligned properly. The red lights flash green when data is transmitted (depending on the baud and data length this is hard to see in some cases). I have observed transmissions from my laptop to the TV but none in reverse. I have tried multiple cables, known to be good. I hope this clarifies some things.

There is no 12V power in the system. If one of the serial devices is not powered then there is no way to get both of the Red LEDs to light on the tester.

Kaptain Kaos

Mitsubishi Television RS-232 woes

I read the manual as defining a straight through connection. NOT a crossover cable.

Easy to miss.

kmkorf

Let me just reiterate my point about the cable. It is NOT the cabling connection. Transmit of AMX goes to Receive of the TV and the Transmit of the TV goes to the Receive of the AMX. This was verified by the cable tester. (See pics in previous post)

Thanks,

Thomas Hayes

I believe what Kaptain Kaos (correct me if I'm wrong, Kaos) was saying that instead of Tx to Rx and Rx to Tx as the normal config. Use Tx to Tx and Rx to Rx.

[Deleted User]

Not sure how that tester works, but why is the CTS/RTS lit? The manual shows no connection for these, simply TX/RX & ground. Also the top two lights are red, those are the ones that matter. Seems like you should get a green light on the top left one if it 'tests' ok.

The cable looks like it should be standard null modem with only pins 2, 3, & 5.

amx

---

mitsu
2

---

3
3

---

2
5

---

5

EDIT:

Just noticed this text in their manual, which i think may be incorrect because it doesn't jive with their pinout:

Wire the cable so that each pair of data lines is straight between the two devices. These data line pairs are RXD
(Receive data) and TXD (Transmit data.).

kmkorf

The tester lights are powered by the serial ports so if you have one device that is a laptop that does support CTS/RTS then one side of the tester lights will illuminate because there is active signal on those lines even if the other side doesn't support CTS/RTS. I agree that the LEDs should be Green for TX/RX but I think our tester was wired backwards at the factory (We had another test at one time and its lights were all green when connected properly). The lights do flash green when there is data going to between devices. If I unplug one of the devices from the tester then the lights associated with that device go dark. So if I unplug the controller from the tester, I still have the 2 lights at the top illuminated. All that this means is that there is voltage present on the CTS/RTS line at the TV. I've seen many devices that light the CTS/RTS light but didn't use it in their communications requirement. My guess is that the rs-232 port is fully functional, they just ignore CTS/RTS.

I will say that I have not tried to use flow control in any of my dinking so I may give that a whirl.

DigiMe

Mitsubishi Television RS-232 woes

To all who were apart of this thread. -->kmkorf - have you come to a soultion to control this unit. I am going to a location tomorrow to program a NI-3000 which will be controlling 2 of the Misubishi WL-82913. If you have, I was wondering if I could see the portion of the code used to control the unit to make sure I am formating my string correctly. Thank you to all,

Jairo Martinez
AMX Programmer
Newcome Electronic Systems
Columbus, Ohio

kmkorf

Ended up using IR

Jairo,

Unfortunately I threw in the towel on this one and we ended up installing an IR flasher inside the actual television while we had it apart for transport to the customers residence. The sensor is actually located through the front screen like most projections televisions of this type. Good luck on your quest.

Regards,
Kurt Korfhage
Managing Partner
Integration Unlimited
ACE Certified Programmer/Designer

DigiMe

Mitsubishi Television RS-232 woes

Forum Thread Group:

I was able to do basic control of the Mitsubishi WL-82913. It took abit to get the command structure right. As mention by another member of this forum, the 232-manual is poorly written and not accurate is some respects.

I was able to turn the unit "ON" and "OFF" as well as pole to see what the power state was:

ON = "$DF,$80,$70,$F8,$02,$00,$00,$36"
OFF = "$DF,$80,$70,$F8,$02,$00,$01,$35"

Power Status = "$DF,$80,$70,$F8,$02,$00,$80,$B6"
Reply ON = $7F,$70,$80,$F8,$04,$00,$80,$00,$01,$13"
Reply OFF = "$7F,$70,$80,$F8,$04,$00,$80,$00,$02,$12"

Of course, I am having issues switching inputs at this time. I hope to have that figured out soon and will update this post with that data.

Jairo Martinez