arduino uno vs nano programming baud rate

I accidentally burn 'UNO' bootloader to my arduino 'NANO' and I notice that the baud rate is faster (11560-uno vs 57600-nano) so my 20kb sketch is uploaded in 3 second instead of 5.7 seconds and everything work fine. I theory UNO and NANO are same uC so is it safe to programmin my NANO as UNO? I upload my sketch very often so it is significant difference for me.
Also I want to know is it possible to increase speed yet more?

smarq8:
I theory UNO and NANO are same uC so is it safe to programmin my NANO as UNO?

Absolutely. I do this with all my Nanos. It also frees up 1.5 kB of program memory and allows you to use the watchdog timer to reset the microcontroller. For most beginners it's not worth adding the complexity of burning the bootloader but it's definitely worth the effort for anyone at a more advanced stage with Arduino.

smarq8:
Also I want to know is it possible to increase speed yet more?

Yes. I know there is a board definition in the Mighty 1284P hardware package that runs the bootloader at 1 Mbps and I never heard reports of people having problems with it. The easiest way to play with higher bootloader speeds is to install MiniCore:

It comes with bootloaders compiled for a variety of speeds up to 1 Mbps. It uses 115200 as default so you do need to edit boards.txt and change 328.menu.clock.16MHz_external.upload.speed= to your desired speed, then it automatically updates the bootloader file name from that property. The available speeds are:

  • 9600
  • 19200
  • 38400
  • 57600
  • 115200
  • 250000
  • 500000
  • 1000000

You need to restart the Arduino IDE before changes you make to boards.txt take effect.

If you want a different baud rate then you will need to compile the bootloader from source, which is not so difficult.

@pert
it work perfectly, 1Mbaudand and time is reduced to 2,2 sec. Also can I somehow to boost speed of my USBASP programmer?