how to connect a serial lcd monitor to a raspberri pi


13 posts
by rakevnihcas » Sun Dec 23, 2012 8:23 am
I ve a LG lcd monitor and it has a serail port.I ve to connect it to a raspberry pi,but raspberry pi does not ve a serial port.I ve to connect it in order to display the output.I thought of using serial to usb converter ,and connect it to raspberry pi.Will that work???or are there any converters available to convert from serial to hdmi so that o can connect it to raspberry pi........please suggest me ......
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by joan » Sun Dec 23, 2012 10:06 am
Could you post a link to the model or a similar model? Something like http://compare.ebay.co.uk/like/190573003243 ?
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by efflandt » Sun Dec 23, 2012 7:35 pm
A serial port on a TV is only for servicing the TV (changing its firmware settings using commands), not for displaying video output. If you muck about in there without knowing proper commands for the TV, you could make it no longer work properly.

If the monitor has DVI, you can connect it as a display for the Pi using a DVI to HDMI cable (both use same digital video signal). DVI does not have audio.

If it only has VGA you would need an HDMI to VGA "converter", preferably with is own power source. HDMI is digital only, VGA is analog only. In many cases a DVI video card can do either HDMI or VGA with a simple adapter and/or proper cable. But HDMI to VGA cannot be done with just cables or adapters alone, it needs a digital to analog video converter.
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by rakevnihcas » Mon Dec 24, 2012 3:00 pm
I ve a LG LCD 14.5" computer monitor,it has only serial port,through which i ve connected it to my cpu.I want do the same thing with raspberry pi,but how to that.I can connect my usb keyboard and mouse to raspberri pi,but how to connect this monitor,which has serial port.I want to connect this to my pi........how to do that........suggest me
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by bgirardot » Mon Dec 24, 2012 3:52 pm
rakevnihcas wrote:I ve a LG LCD 14.5" computer monitor,it has only serial port,through which i ve connected it to my cpu.I want do the same thing with raspberry pi,but how to that.I can connect my usb keyboard and mouse to raspberri pi,but how to connect this monitor,which has serial port.I want to connect this to my pi........how to do that........suggest me


Does the port have 2 rows of holes or 3 rows of holes?
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by efflandt » Mon Dec 24, 2012 5:43 pm
How many pins does the "serial" port have? A serial port usually has either 25 or 9 pins.

If it is sort of a D shape and has 15 pins it is likely a VGA port. If that is the case you would need an HDMI to VGA "converter" that would convert HDMI digital video to VGA analog video. That cannot be done with a simple cable or adapters since the video signal is different.

If that is the only port the monitor has, it may not have a DVI port, which is a bit more rectangular and has more pins, or at least more places for pins, since it can potentially do analog and digital video. If the port is DVI, you would only need an HDMI to DVI cable, since the digital video on DVI and HDMI is the same.

http://en.wikipedia.org/wiki/List_of_video_connectors
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by rakevnihcas » Sat Dec 29, 2012 1:31 pm
It is a LG company 14.5'' LCD monitor.It has serial port DB9(9 pin).
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by techpaul » Sat Dec 29, 2012 1:59 pm
Be wary of thinking it is a serial monitor. It MIGHT be a serial terminal type monitor, but it could also be an RGB monitor using a 9 pin D type connector, with video signals NOT serial signals.

If that is the case connecting a serial port to it WILL damage the monitor input.

Look on the monitor find its model number and do a search for LG and the model number and find the manual or at least something that specifies ALL the connectors and what they do.

In some cases it may only be a serial port to control brightness, contrast, input soiurce.

Without the EXACT model number and the connector scheme you are clutching at straws.
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by rakevnihcas » Thu Jan 03, 2013 7:57 am
It is a vga port with 15 pins in three rows.How much would the vga to hdmi converter cost.................................any other cheap converters available....suggest me
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by rakevnihcas » Fri Jan 04, 2013 8:36 am
someone suggest me..........any cost effective methods to convert from vga to hdmi...................
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by bgirardot » Fri Jan 04, 2013 1:07 pm
There is this list of adapters that people have found to work, but they are just people's reports and are not really a guarantee:

http://elinux.org/RPi_VerifiedPeriphera ... rter_boxes

I believe the two most important points in an HDMI - VGA adapter are 1) that it be an "active" adapter and 2) that it have its own power supply

My understanding is that "active" means there is electronics in the device that convert the signal to analog.

And since they have electronics doing the conversion, they draw power and the Raspberry Pi can not supply very much power on the HDMI port and you risk damaging the Raspberry Pi as some adapter will draw more than they should, so you are safest if you get one that has its own external power supply to make sure it does not draw from the RPi.
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by rakevnihcas » Sat Jan 05, 2013 9:08 am
Thanks a lot for ur suggestion.I just saw a you tube video in which someone has used a usb video capture card through which he has connected to RCA video output on pi,and through usb on his computer.A video player will be available with that capture card.He just opened the video player and did some settings.and thats it...........so which is the best method whether a usb video capture card or vga to hdmi converter
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by amitnu009 » Wed Mar 06, 2013 6:07 pm
rakevnihcas wrote:Thanks a lot for ur suggestion.I just saw a you tube video in which someone has used a usb video capture card through which he has connected to RCA video output on pi,and through usb on his computer.A video player will be available with that capture card.He just opened the video player and did some settings.and thats it...........so which is the best method whether a usb video capture card or vga to hdmi converter




i bought the capture card on ebay and tried to connect as was shown on video..but it didnt work for me..still trying to figure it out...
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