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i recently posted a question, but didn't had an answer (my fault :) ). my question wasn't straight-forward and clear.

so my final goal is to communicate between nodered (raspberry-pi) and my lg tv. I'm getting stuck on every step I take... So I will try to start step by step. so to begin I wanna try controlling the tv with my windows laptop. I tried putty, but I think that's not the right program to use. my final goal is to controll the power-saving to turn the screen off, turn the tv on and off, and controll the volume. I also want feedback so my home-automation knows the state and volume of the tv.

so I think it's maybe good to start with a right program on my computer to start troubleshooting? so my first (and hopefully my last :p )question is: Is there anny good program that can send those commands and reicieve the data back from the tv? and second, it's not so clear what commands to send to the tv. in the text below is my previous question, are those commands usable?

I want to controll my LG tv using a raspberry pi running node-red. I'm havving troubles to get it to work. i readed the following LG RS232 Commands partially working, but I'm just getting stuck every time.

So what I have is a raspberry pi running nodered, i can connect nodered with the serial device ttyUSB0. (its a usb to serial adapter, with a crossover block female to female). i connected everything, but i get nothing out of my tv. I tried using putty on my windows, but i keep getting stuck :/ this forum is my last hope :p

edit: on page 142 of this PDF are the instructions for the tv https://gscs-b2c.lge.com/downloadFile?fileId=KROWM000259057.pdf

edit:I the tv uses rs232 the adapter I used is a usb to rs232 adapter :https://www.aliexpress.com/item/4001296387344.html?spm=a2g0s.9042311.0.0.27424c4dF9z9ML with a connector (female female): https://www.aliexpress.com/item/4000564124562.html?spm=a2g0s.9042311.0.0.27424c4dF9z9ML

my settings: baud:9600 data bits 8 paririty none stop bits 1 dtr, rts, cts, dsr are all auto

most cammands that i tried are gone, but i tried those ones: ka 01 ff[CR]

ka 01 ff

ka 01 00[CR]

ka 01 00

[K][a][1][ ][][00][x]

[K][a][1][ ][][01][x]

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2 Answers 2

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Try Realterm:

enter image description here

The shown commands should turn the TV on and off, if I read the manual correctly.

As the other answer suggests, also make sure that TxD/RxD are not swapped (pins 2 and 3 on the DE-9 pinout).

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  • \$\begingroup\$ thanks for helping me out! i'm first going to buy a crossover adapter (to keep it clean without solder). \$\endgroup\$
    – madness007
    Commented Mar 17, 2021 at 8:50
  • \$\begingroup\$ @madness007 Before PCs came along and sort-of standardized the interface that was always happening. \$\endgroup\$
    – Spehro 'speff' Pefhany
    Commented Mar 17, 2021 at 8:51
  • \$\begingroup\$ well, I thought that such adapter was a crossover.. well it was less than an euro so doesn't matter. \$\endgroup\$
    – madness007
    Commented Mar 17, 2021 at 8:53
  • \$\begingroup\$ Oh, it was much worse than crossover cables. Handshaking, for example. \$\endgroup\$
    – Spehro 'speff' Pefhany
    Commented Mar 17, 2021 at 8:55
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The adapter you have does not connect the pins correctly as per the TV requirements.

You can verify this yourself by checking the adapter link for the connections it makes, and the TV manual for the connections required.

TV manual explicitly says a crossover cable is needed.

The gender adapters in general never change the wiring and do not provide a crossover connection.

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  • \$\begingroup\$ Thx for that! I'm buying a crossover adapter. \$\endgroup\$
    – madness007
    Commented Mar 17, 2021 at 8:50

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