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Phil23
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Joined: 27/03/2016
Location: Australia
Posts: 1667

Posted: 01:50am 26 Jul 2016

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Just wondering what's best practice?

Open Com1 before the main loop & leave it open till whenever?

Or, should it be opened & closed within this Sub?

[Code]
Sub SendData
Local Null$=INPUT$(LOC(#1),#1) 'then suck everything in the buffer out and stick it in Null. Just for now. Will Check the call ID it later...

'Add Jim's CRC Check in Later.

Print #1,"Air Temp=";Str$(TmpHpAir,3,2);"#"
Print #1,"EvapTemp=";Str$(TmpHpEva,3,2);"#"
Print #1,"CompTemp=";Str$(TmpHpCmp,3,2);"#"
Print #1,"Inp Temp=";Str$(TmpHpInp,3,2);"#"
Print #1,"Out Temp=";Str$(TmpHpOut,3,2);"#"
Print #1,"Loop Num=";LoopCount

End Sub
[/code]

Thanks

Phil

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9590

Posted: 07:14pm 26 Jul 2016

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I always open the COM port and leave it open forever.
That is just me though.
There is no law that says you should close it.
The serial-port buffers will look after any data for you.

It does very-much depend on what you are doing.

Does LOCAL work like that?
I know you can use it to define local variables, but can you use it to define a local-only variable AND assign it data at the same time?
In any event, it will only EVER check the serial-port and suck the data out of it, when it runs that LOCAL command, which it only ever does once, so I would still prefer to put the Null$=Input$ elsewhere.

Again - just my 2c.
Others here will say if it is OK to use LOCAL like that, and if it is, then I have learned something new myself.

Smoke makes things work. When the smoke gets out, it stops!

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10222

Posted: 08:18pm 26 Jul 2016

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Quote Others here will say if it is OK to use LOCAL like that, and if it is, then I have learned something new myself

It is absolutely OK to use LOCAL like that. The statement is run each and every time the subroutine is called. LOCAL variables only exist when the subroutine is running. Any memory used is returned to the pool when the subroutine exits.

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9590

Posted: 02:35am 27 Jul 2016

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Okey dokey, thanks for that - I have updated my memory.

Smoke makes things work. When the smoke gets out, it stops!

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