View Full Version : controlling an LCD projector

12-04-2006, 10:04 AM
I want to control a Panasonic PT-AE900U digital projector using its serial connection. I need to switch it out of and into standby based on inputs from the Parallax PIR sensor.

The owner's manual, in the section on serial control of the unit, asks for the following block of code;

STX/Command/:/Parameter/ETX (I have subtituted slashes for the divisions in the little box wherein this is illustrated on the page)

It then states that "STX" is the start byte (02h)
"Command" is three bytes
":" is one byte
"Parameter" is one to four bytes
and "ETX" is the end byte (03h)

The command for Power on is PON
the command for Power off is POF

Other info:
Signal level RS-232C
Sync. Method Asynchronous
Baud Rate 9600
No Parity
Character Length 8 bits
Stop bit 1 bit
no X parameter
no S parameter

In my case I have no need for parameters as I am just switching it on and off so the manual says I don't need the colon.

I got it all hooked up and I ran what I thought was the correct code using SEROUT from a BS2 and got nothing. The computer that has that program saved on it is now dead otherwise I would include it but as it is I have to start from scratch (probably a good thing). I think it went something like this;


So my question is; Assuming my physical connection is correct, and that I have figured my BAUDMODE correctly (a huge assumption considering my lack of experience in serial) what should the code that gets sent using the SEROUT command look like in order to get the projector to do what it's told? I am not using a driver, just plugging straight into the serial input on my homework board.

If I have the code in hand then I can start looking at other variables to figure out what else might be wrong. If I've left any details out please ask and I will try to provide


Phil Pilgrim (PhiPi)
12-04-2006, 11:34 AM



SEROUT 16, 84, [STX, "PON", ETX]

STX and ETX are the names of ASCII control characters whose values are 2 and 3, respectively.


12-05-2006, 06:48 AM
Thanks Phil, I'll let you know how it goes.