Programming an Arduino without USB

Just out of curiosity - if i finally had my breadboard arduino without usb… would it be possible to program it with such a thing?

If i get the architecture of the arduino right all i had to do was to wire RX and TX to Digital Pins 0 and 1
Is that somehow right or totally wrong?

Sorry it`s not that easy !!!

The levels have to be converted to TTL 5v , from standard rs232.
So you will still need a some form of buffering .

meeeehhh… that is simply not fair. The more i see about such rather simple things the more i understand what a freaking kind of hardware the arduino actually is. whats the TTL converter? is it part of the FTDI chip?

k there are 3 protocols we are dealing with here

USB, TTL and Serial (this is greatly simplified. Technically they are all forms of serial communication)

The FTDI converts USB to TTL
the “dongle” you linked converts USB to Serial

If you use the dongle you then need to convert the serial to TTL. You would have to use the MAX232 chip to accomplish this.
Then you would be going USB->Serial->TTL

oh i see, i thought ttl was just some sort of amplified serial…
thanks for clearing that up

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i thought ttl was just some sort of amplified serial…

It’s sort of the other way around: RS232 is an amplified (and inverted) TTL, so that we can communicate over greater distances than TTL allows.


ok, thanks.