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--- arduino:unofaq [2010/09/28 18:59]
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+++ arduino:unofaq [2010/09/28 20:05]
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 The first popularly manufactured Arduino was called the NG (New Generation, like Star Trek, yknow?) The NG used the Atmega8 chip running at 16 MHz and an FT232 chip for the USB interface. The bootloader takes up 2KB of space and runs at 19200 baud
-The next version was the Diecimila. The Diecimila updated the chip from the Atmega8 to the Atmega168. The great thing here is double the space and memory (16K instead of 8K). It still ran at 16MHz. The Diecimila also added two extra header pins for 3.3V (from the FTDI chip) and the reset pin which can be handy when a shield is covering up the Reset button. The bootloader takes up 2KB of space and runs at 19200 baud
+The next version was the Diecimila. The Diecimila updated the chip from the Atmega8 to the Atmega168. The great thing here is double the space and memory (16K instead of 8K). It still ran at 16MHz. The Diecimila also added two extra header pins for 3.3V (from the FTDI chip) and the reset pin which can be handy when a shield is covering up the Reset button. The bootloader takes up 2KB of space and runs at 19200 baud. Auto-resetting was also added which makes life awesomer for everyone.
 In 2009, the Duemilanove was released. This one also upgraded the chip again, to the Atmega328. Yet another doubling of space and memory! Another upgrade is now the power is automagically switched between USB and DC-jack which removed the previous jumper. This makes it easier and faster to move from programming to standalone and got rid of some confusion. The bootloader takes up 2KB of space and runs at 57600 baud
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   - Having the chip act only as a USB/serial passthrough simplifies the firmware so that the chip has only one function instead of having to have it do double duty as programmer -and- serial interface (think about it, its not easy)
   - Backwards compatibility - the Arduino chips can still be programmed with FTDI breakout boards or cables, making it easy for people to breadboard or make clones.
+====== How does the new '8u2 affect Arduino-derivatives? ======
+Every USB device needs to have a unique product id and vendor id. Vendor IDs (VID) are sold to companies and Product IDs (PID) are chosen by that company. So for example FTDI owns VID #0403 and they give their chips ID's between #0000 and #FFFF (65,536 different PIDs) Older Ardiuno's used FTDI's VID/PID as that is part of the deal when you purchase their chips. Because the Uno does not use an FTDI chip anymore, the Arduino team had to purchase a USB Vendor ID (VID). Every Arduino product will now have their own PID starting with the Uno (#0001)
+If you want to make your own Arduino-compatible board, you have a few choices:
+  - Don't use an 8u2, go with an FTDI chip instead that comes with a VID
+  - If you're planning to make more than one board for your personal use, you will have to [[http://www.usb.org/developers/vendor/|purchase a VID from USB IF]] for a one time $2000 fee
+  - If you're making a single board for your own experimentation, you can pick a VID/PID that doesn't interfere with any devices on your computer and substitute those in
+  - You can purchase licenses for single VID/PID pairs from companies that develop USB devices (we dont have any specific links at the moment)
+However, you can't use the Arduino VID when distributing your own Arduino-compatibles! If the cost of a VID is too much for you, simply go with an FTDI chip, 'K?
+===== I tried to find a place to buy some '8u2s and couldnt locate any! =====
+Yep, there is a worldwide shortage of Atmel parts right now. Even the chip used in the Arduino core (Atmega328P) is really hard to get. This happens after recesssions. We hope that these and other Atmel chips will show up again in places like digikey soon. Till then, keep searching on findchips.com!
+===== So does this mean there may be a problem making Arduinos? =====
+Probably not. The Arduino team buys chips in the 10's of thousands, directly from Atmel. They probably get priority over distributors because of this. We're assuming the team bought enough to last for a while
+===== Did the Arduino team move from the FTDI chip to the '8u2 to screw over derivative-makers? =====
+While the appearance of a hard-to-get chip coupled with the VID/PID mishegas may seem to be a little annoying, we don't think that means that the Arduino team is being malicious or attempting to make life difficult for people who make derivatives. The move to an '8u2 makes the Arduino more powerful, and easy to use as there are fewer drivers to install. While there is a shortage now, there will eventually be plenty of chips on the market.
+Some people in the Arduino forum have thought of forming a group that would purchase a VID for Arduinites to use in personal projects. This is a pretty good idea and its probably the best way to avoid VID/PID conflicts. Between 65,536 projects, that comes to under a nickel per PID.
+And of course, because they didn't get rid of the bootloader system, you can **always** just use an FTDI chip
 ====== Are Shields still going to work? ======
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 Yes! The Uno is still available under a Creative commons license. [[http://arduino.cc/en/Main/ArduinoBoardUno|You can get the latest schematics and layouts over at the Arduino website.]]

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