LG M4212 and Smart-E
mshunt
Posts: 23
Howdoo,
I've got a problem with controlling LG M4212 LCD monitors through Smart-E Cat5 video converters. You can send RS232 through the cat5 video distribution system and sometimes it works, but particularly the power on and off strings for these monitors gets there infrequently, or not at all. I can send the command on it's own via control a device, but when I send the same string when triggered in the program nothing happens, or it takes a couple of instances for the command to work.
Any ideas?
The string for power on and off is
'ka 0 1',$0D
Where ka is the command, the first 0 is the address, set to global in this case, and the 1 is the power status. Comm settings are 9600 N,8,1 I've tried sending discrete strings selected with a switch case or IF statements, building the string with the power status request selected by a variable, sending the string first before anything else, sending it last, nothing appears to work. But again, I can send the command on it's own via control a device and it works every time. And other commands work from the code, volume level, source selection, auto image etc. All good.
If anyone has any ideas i'll happily try them.
I've got a problem with controlling LG M4212 LCD monitors through Smart-E Cat5 video converters. You can send RS232 through the cat5 video distribution system and sometimes it works, but particularly the power on and off strings for these monitors gets there infrequently, or not at all. I can send the command on it's own via control a device, but when I send the same string when triggered in the program nothing happens, or it takes a couple of instances for the command to work.
Any ideas?
The string for power on and off is
'ka 0 1',$0D
Where ka is the command, the first 0 is the address, set to global in this case, and the 1 is the power status. Comm settings are 9600 N,8,1 I've tried sending discrete strings selected with a switch case or IF statements, building the string with the power status request selected by a variable, sending the string first before anything else, sending it last, nothing appears to work. But again, I can send the command on it's own via control a device and it works every time. And other commands work from the code, volume level, source selection, auto image etc. All good.
If anyone has any ideas i'll happily try them.
0
Comments
The LG serial ports are notoriously flaky. We've had such a bad experience with them we've quit selling them altogether in systems that require control systems.
My guess is that you might check the voltage of the RS232 output of the Smart E. It might be just on the edge of spec. Combine this with the flakiness of the port in general, you might have a bad combination. Just a guess.
That's actually what occured to me. Which kind of explains why it works on it's own, but not as part of the code where other RS232 codes are being broadcast across the same RS232 network.
I guess one solution is to address each CAT5 port individually which can be done and send the appropriate string to each device in turn. ( I have a mix of LG monitors and Panasonic projectors) This would also give me feedback from each device to prove that it is getting the command.
Here's one: http://www.sena.com/products/device_servers/
--John
--John
In terms of the hardware configuration, the rs232 goes through the smart-e along with the video down the CAT5, to simplify the code, I've just been broadcasting the commands to all devices, as there's a mix of LG and Panasonic projectors on the same CAT5 distributor. The downside to this method is it appears to be confusing the LG's on some commands. I've used the same code but wired directly to the AMX, and it runs fine.
It's been suggested that I could put $0D before the command too, I guess to let the LG know the last command has finished and the next one is a new command. It needs to be tested so we'll see how it will work out.