Telnet half-duplex possible?

I've been looking at some Hubitat documents however telnetConnect stated it has options but doesn't state what they are.

There is an error in what seems to be my driver but I can't verify that without putting telnet in half-duplex mode like the documentation for their API says to do.

Is it possible?

You may be out of luck on options.

You are telling me that nobody here can tell me what options there are to select from? The same people that wrote this protocol?

That is like telling me that Domino's Pizza gives options for toppings on pizza but refuses to tell you what they have available. Matter of fact, it's exactly like it.

Quite funny indeed.

I have come across this hurdle a few times in my development with hubitat. I can understand wanting a closed-source codebase for IP concerns... but when you are a small team with a closed-source codebase... and rely heavily on community support from other developers... it can become a challenge. I can't say how many times I have found myself throwing random actions at a function.. hoping one of them will "stick".

What is the issue you are experiencing? I've only written two small apps using telnet for my audio/video equipment... but maybe I can provide another set of eyes.

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List<Integer> termChars: default [13,10]
List<String> ignoreList: default []
boolean multiThread: default false
boolean byteInterface: default false
boolean persistentMessages: default false
boolean asyncConnect: default false

example with a few options
telnetConnect(ip, 23, "lutron", "integration", ignoreList:["GNET> "], termChars:[10])

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I was merely linking to another post which appeared to state only one option was available.

It's a connectivity issue with Denon, even with the built in driver.

When it starts happening, I usually have to take the Denon offline for a few hours by disabling the port on my switch or force it to use the WiFi, sometimes even fully reset the network section of the Denon

Other times, it can also be solved by rebooting the switch.

But, when it starts happening, it will go offline on the driver and a manual connect will show you either a slew of output it has stuck and/or just erroring out with "Connection closed by a foreign host"

As it stands, telnet is full-duplex on my driver and I expect the same with the built in driver. If these drivers are talking to the amp in an unsupported way, this could be the issue.

@mike.maxwell might be able to change the built in to half-duplex and we can start there.

This problem is not fun to deal with every 36-48 hours.

They aren’t, I use the denon driver in production with my Marantz AV10
The only options we use in production drivers are term chars and ignore list

So, it's HDX on the built in driver, glad I know this so I can figure out what else may be causing this issue.

I might take my driver to HTTP control instead of telnet. I never lose app control. Reading up, it's definitely possible.

Correct everything is full duplex (asyncConnect: default false), as far as telnet itself goes, there isn't anything called half duplex, at least nothing that I've ever seen. Have you tried an external IP to serial adapter, like a global cache flex?
This wouldn’t be the first time I’ve seen a built in Ethernet port go south…

Full duplex is incorrect:

I mean, it works but can't accurately assess it when it's sending commands at FDX.

that's the serial port where that would matter, has nothing to do with ethernet, telnet or the driver, that part having to do with ethernet is the connection to the port, that's also nothing to do with the driver.
Try connecting with a desktop telnet client, see if the connection drops or whatever its doing...

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That's how I figured out what it's doing, with a desktop client.

It connects, gives a stream of data that looks like it could be cached up, then "Connection closed by foreign host"

Or, it will say that same thing without the stream of data.

I'm tempted to invest in a StarTec USB to DB9 and try using eventghost on my HTPC for a while. Surprisingly, the EG plug-in has a lot of functions, even more than my driver.