Why Not Just Use The '8u2 As A Programmer?

1.	Why Not Just Use The '8u2 As A Programmer?
Answer» While it is possible that the 8u2 could act as a full ISP PROGRAMMER there are a few reasons why its GOOD that it isn't. Giving beginners access to a full ISP programmer will result in bricked chips. There's no risk of MESSING up the Arduino chip beyond RECOGNITION if it's just being bootloaded 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. While it is possible that the 8u2 could act as a full ISP programmer there are a few reasons why its good that it isn't.

Answer»

While it is possible that the 8u2 could act as a full ISP PROGRAMMER there are a few reasons why its GOOD that it isn't.

Giving beginners access to a full ISP programmer will result in bricked chips. There's no risk of MESSING up the Arduino chip beyond RECOGNITION if it's just being bootloaded
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.

While it is possible that the 8u2 could act as a full ISP programmer there are a few reasons why its good that it isn't.

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