Program upload speed - Uno vs Nano and something strange

Projects Programming
1

I developed a project on the Uno and now moved it to the Nano (V3.0 with ATmega328, according to the ebay seller) to save space. What I noticed are two strange things:

  1. It take about twice as long to upload the same program to the Nano opposed to the Uno (a 15K program).
  2. In my void setup() I play a short beep sound from a piezo buzzer. One the Uno, when I power the device, it beeps once as it should. On the Nano it beeps once and after about 5-10 seconds it beeps again, as if it reseted or something. After that, the two (Uno and Nano) behave the same.

Any ideas?

2

Is your Nano a 3.3V (8MHz) model or a 5.0V (16MHz) model?

3

It's supposed to be 16MHz... How can I tell?
http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=270845858275

4

I wouldn't believe anything from the electronics experts at eBay.

The best way to tell what you have is to physically look at yours, not a picture in an eBay listing.

The upload time and power behavior could be the rest of an older bootloader being programmed onto the Nano.

5

Set the upload options to verbose and have a look at the upload speed passed to avrdude.

6

I looked at the baud rate avrdude is using and it is indeed 57600 and not 115200...
I tried to upload using 115200 using the command line avrdude but that didn't work...

Using the following works fine:

avrdude.exe -C avrdude.conf -patmega328p -carduino -P\\.\COM14 -b57600 -D -Uflash:w:SpeedCam.cpp.hex:i

But using the following, I get an error saying "avrdude.exe: stk500_getsync(): not in sync: resp=0x00":

avrdude.exe -C avrdude.conf -patmega328p -carduino -P\\.\COM14 -b115200 -D -Uflash:w:SpeedCam.cpp.hex:i

Can it be that my Arduino Nano is 8MHz and not 16MHz?

7

What speed is the crystal on the board? It should be written on top.

8

I'll have to take my project apart... it's buried deep inside :frowning:

9

I'm not sure why you would bother. What you describe is behavior of the bootloader+boards behavior.

Unless you are selecting a board with 8MHz support in the Boards menu, you already know what the clock speed of your Arduino is.

If you've already built your project around the board you have, why do you care if it takes slightly longer to upload?

10

James, you are right. It just bothered me that the Uno and Nano that should be the same in terms of upload speed and clock speed, act differently...