AVROSP COM port limitation

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#1
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Hello,
I'm using AVROSP with a Xmega device, but my question is relative to AVROSP itself.
My board include a FT232 USB converter, that is used for the bootloader upgrade.
With FTDI drivers, in standard installation, every new FT232 device create a new COM port number (on my desktop, I'm reaching COM36 now). Moreover, every SPP bluetooth device create also new COM ports numbers..
But the AVROSP is limited to port COM#8 maximum !
Can somebody explain me why is there this limitation ?
How can I suppress it and handle high COM ports ?

Thanks !
Aurelien

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Use the Device Manager to change the COM port #.

Warning: Grumpy Old Chuff. Reading this post may severely damage your mental health.

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Hello,
Thank you, but I don't think that my customers will accept such a constraint...
I'm not specialized in PC software programming that's why I posting this request...

Thanks you
Aurelien

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Use avrdude instead of AVROSP.

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OK...
My bootloader is already developped with the AVROSP protocol, and finding good software was difficult, I've tried saveral ones before finding a good version !
I just want to know WHY there is a limitation on AVROSP software for COM port. Just to know if this is a choice of the developpers, and is there any other aspect that I miss ?

Aurelien

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Like I say "avrdude -c avr911" - what's the problem with using that?

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Maybe because I'm not sure that it will work with AVR Xmega, since the AVROSP in AVR911 does not work, while the AVR1605 version is adapted to my micro.
What is your problem with AVROSP ?

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Quote:

What is your problem with AVROSP ?

Not sure who that question is directed at? I thought it was YOU that had the problem? You said you were using some PC software that would not access high comm ports. I gave you the name of an alternative PC program that speaks the same (AVR911) protocol, can interface to virtually any tiny/mega/xmega ever made and has no limit on COM port numbers. So why do you think *I* have a problem?

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I just say that because I want to know the reason why AVROSP is limited on COM port, and I get answers for others software !
So I will try other software if necessary, but in the meantime, I just want to know the reason of the limitation, if somebody knows it !

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Quote:

, I just want to know the reason of the limitation, if somebody knows it !

Surely it's because the guy who wrote it presumably thought "well no one's ever going to use a COM port greater than 9 are they?". If you are old enough to remember you'll recall that PCs used to have D25 serial ports. Later on when the 80286 based IBM AT came out IBM switched to using D9 for serial and some PCs even had two called COM1 and COM2. Still later on there were even PCs with four called COM1, COM2, COM3 and COM4. Some companies made ISA plug in cards that could add as many as four more serial ports (likely numbered COM4..COM7). I'm guessing AVROSP was maybe written on a computer such as this and the very idea of having a COM port about 8 was almost unheard of. Then this new fangled serial bus called USB was invented in about 1995 - it took a few years to catch on and only in later versions of Win98 was it finally supported by Windows. A year or two after that computer makers thought they could maybe makes PCs without D9 as users could use USB-RS232 to connect to "legacy" devices if they needed. This was maybe around 2000-2002? It was around that time that AVROSP was developed so the idea of VCOMs with high COM numbers was still a very specialised thing.

Ten years later and here we are - things are a bit different now.

The difference with a product such as avrdude is that it's an on-going development and it keeps being updated to reflect new technologies. AVROSP on the other hand should have been put out to pasture a while back.

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OK, thanks. So, if I understand well, this is only a legavy from the old way to code the application ?
Do you think that it is possible to bypass this limitation by modifying the function that call the serial port to open more than COM8 ?

Aurelien

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Quote:

Do you think that it is possible to bypass this limitation by modifying the function that call the serial port to open more than COM8 ?

This is like banging one's head against the wall. Don't you get it? If AVROSP won't get to where you want to be then avrdude has no COM port limitation and "speaks" AVROSP. What is your objection to using avrdude??

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Because I don't know how to download that F...... software ! All link leads to documentation !

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Thanks
It is the latest version ?
I see here that latest version is 5.11 :
http://savannah.nongnu.org/forum...
But I don't find the link to download it...

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That is 5.10 - the copy that ships with WinAVR20100110 - works for most people (unless you want something real new like TPI).

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Quote:
But I don't find the link to download it...
Then you aren't looking!
Menu = Main / HomePage / DOWNLOAD / Docs...

--greg
Still learning, don't shout at me, educate me.
Starting the fire is easy; the hardest part is learning how to keep the flame!

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Oh sh.. I went directly to the end of the page and all I have found was the doc...

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Quote:

Do you think that it is possible to bypass this limitation by modifying the function that call the serial port to open more than COM8 ?

I strongly agree with clawson about using avrdude. However, since you ask, modifying the original AVROSP to support more than COM8 is trivial too - I had to do it once, some time back. I have attached the files I modified and a built executable in the zip. It is a quick and dirty job, but works up to COM99.

Attachment(s): 

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Thanks you th33lf, I was expecting to do such a minor modification because it seems to be the only steps where the COM port limitation acts (and i'm not very skilled on PC software programming).
But, I will also follow the advices of the others guys and try AVRDUDE ;)

Aurelien