RS-232 return from a Hitachi Plasma

Thorleifur

Getting a weird code from a Hitachi Plasma screen (55PMA500E). When using a RS-232 program like Docklight I get the correct response, but when I do this in Netlinx Studio I get something completly different.

Supposed to get: 02 30 30 30 3X 03 (HEX Character Code), where 02 and 03 are the open and close bits.
Am getting via Netlinx: 2D 70

Serial port is set up correctly in the Netlinx and the string is of right length. Any ideas?

NMarkRoberts

It seems to me that you are either sending something different from what you think, or that you are actually receiving something different from what you think. So you need absolute confirmation of both. Here are some ideas:

(a) Use device notifications to watch what is actually being sent and received by your code.

(b) Use "Control a device" to send the string from your controller and watch notifications.

(c) Plug Docklight into your controller, not the Hitachi, and use notifications to see what you are sending.

Note that the problem might just be timing - the code is grabbing the reply before it all arrives - or the setup of the device is wrong so sent or received strings are subtly garbled.

mritz

I think that Hitachi has the same protocoll using on their different models of plasma displays. I did some small programm in 2004 for basic functions like switching on / off and changing the inputs of such a display. First it was not easy to do, but I got a reference doc about Hitachi Plasma - RS232c from Hitachi. I remember that it was very important on this models to first of all send a hex-code to enter the terminal-mode of the display. Without this, the commands send to the display are ignored.

to enter the terminal-communication mode is: send_string dvPLASMA,"$05"
power on is send_string dvPLASMA,"$02,$36,$45,$30,$30,$30,$30,$30,$30,$30,$30,$30,$31,$03"
power off: send_string dvPLASMA,"$02,$36,$45,$30,$30,$30,$30,$30,$30,$30,$30,$30,$30,$03"
and to end the terminal-communication mode: send_string dvPLASMA,"$04"

It is important to end the communication if you also want to use the ir remote control with the display. Otherwise you can ignore it.

Also when sending the $05 code to enter the terminal mode, wait approx. 4 seconds before sending the next commands.

Maybe this helps you?


Regards

Markus Ritz
Mediasystem, Austria

Thorleifur

I can control the Plasma fine. Everything I send at it works. It?s just I have to use the returns to check which input I am using and so forth.

Tried everything and still getting the wrong return. But thanks guys.