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pmuldoon
Joined: 26 Sep 2003 Posts: 218 Location: Northern Indiana
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USB VID number |
Posted: Tue Jan 22, 2008 10:36 am |
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I am upgrading a PIC design from RS232 to USB.
All I need is to look like a COM port, like a USB-RS232 converter cable would do. I merely need to connect to Hyperterminal and possibly a VB program I would write using the serial driver.
Can anyone tell me if I need to purchase a VID license, or are there generic numbers available for such simple interfaces? |
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Ttelmah Guest
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Posted: Tue Jan 22, 2008 10:59 am |
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You have three choices:
1) Buy a full license. Advantage is that you can then have your own 'name' for the device, and it is your product.
2) Use one of the 'demo' numbers, like those from Microchip, and CCS. Downsides are that these _will_ be used by other devices, and are not really meant to be used for a 'marketted' product (testing only).
3) Rent/buy a small 'subset' of the PID numbers available on a VID. For example, FTDI, for their RS232 converter chip, will supply small ranges for a specific product. There are also some license holders, who will sell a small range of numbers on a similar basis. This is cheap, avoids the possibility of a second, different device having the same VID/PID, but puts you into a bit of a 'grey area' in the licensing. Personally, I think it is an acceptable solution for limited 'run' devices.
Best Wishes |
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treitmey
Joined: 23 Jan 2004 Posts: 1094 Location: Appleton,WI USA
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Posted: Tue Jan 22, 2008 2:06 pm |
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For what its worth,.. I used option 3. FTDI gave me a range of 8 addresses.
((3 are used so far)) |
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pmuldoon
Joined: 26 Sep 2003 Posts: 218 Location: Northern Indiana
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Posted: Tue Jan 22, 2008 2:18 pm |
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Thanks, guys.
So that means that every different keyboard, every different thumbdrive, etc has a unique VID/PID # even though they (all thumbdrives, for instance) look the same (an external file store) to the PC.
It just sounds kind of limiting, only 65,000 different mfrs, and each having only 65000 different product models...kind of like the old 640K of ram (or does anybody remember that anymore?)
At $2000 per VID that's about $130,000,000 just to sell numbers.
Thanks again for the input. |
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treitmey
Joined: 23 Jan 2004 Posts: 1094 Location: Appleton,WI USA
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Posted: Tue Jan 22, 2008 2:20 pm |
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My numbers were FREE ![Very Happy](images/smiles/icon_biggrin.gif) |
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pmuldoon
Joined: 26 Sep 2003 Posts: 218 Location: Northern Indiana
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Posted: Tue Jan 22, 2008 2:30 pm |
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That IS a good deal. Too bad I'm not using their chip. I'll probably end up using one of the PIC's with the built-in USB. It sounds incredibly easy from the hardware standpoint - just add a USB connector. The software sounds just complicated enough to keep it interesting. If it goes well, I will try to make it a USB on-the-go and r/w to thumbdrives as well. then I can write my very first bootloader and...well, you know. Just add stuff til it breaks and then optimize. |
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Ttelmah Guest
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Posted: Wed Jan 23, 2008 3:26 am |
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The VID/PID problem still exists using the PIC's own hardware. However buying a 'block' of PID's, is really cheap (the last time I looked, you were talking only a very few dollars for this). There also used to be a cheaper way of getting a VID. If I remember right, it was cheaper to join as a 'USB developer', which gave you a free VID, than to buy the VID. USB 'OTG', normally involves hardware supporting being a USB 'master' device. The PIC _does not_ support this. If you want to do this, you need to look at a chip supporting this (simplest, is probably the FTDI 'Vinculum').
Yes, the VID/PID system, is a limit (and a 'moneyspinner'), but there is a potential extension built into the standard (the idea was to use one of the 'reserved' transaction bytes, to say 'extended VID' when necessary. Just like switching to IPV6 to extend the address range.
Best Wishes |
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pmuldoon
Joined: 26 Sep 2003 Posts: 218 Location: Northern Indiana
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Posted: Wed Jan 23, 2008 7:00 am |
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I wasn't aware that the PIC's built-in USB interface didn't support OTG - thanks for the info. |
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bwhiten
Joined: 26 Nov 2003 Posts: 151 Location: Grayson, GA
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One PID for free |
Posted: Mon Jan 28, 2008 6:39 pm |
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I just received my personal PID from Microchip. This is good for as long as you use it ONLY for Microchip based USB devices. |
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