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Topic: Baud rate for uploading your sketch (Read 12118 times) previous topic - next topic

Techone

My quick question is :

What is the typical baud rate when the IDE <-- mine is 022   upload a sketch ?


retrolefty


My quick question is :

What is the typical baud rate when the IDE <-- mine is 022   upload a sketch ?





No typical, the baudrate used is determined by the specific bootloader code burned into your chip. Of course that must match the baud rate used by the IDE which uses the select board menu which in turn is obtained from the baudrate value stored for that board selection in the boards.txt file.


Techone

So I will find that info in boards.txt.

OK ... here a section:

Code: [Select]

uno.name=Arduino Uno
uno.upload.protocol=stk500
uno.upload.maximum_size=32256
uno.upload.speed=115200
uno.bootloader.low_fuses=0xff
uno.bootloader.high_fuses=0xde
uno.bootloader.extended_fuses=0x05
uno.bootloader.path=optiboot
uno.bootloader.file=optiboot_atmega328.hex
uno.bootloader.unlock_bits=0x3F
uno.bootloader.lock_bits=0x0F
uno.build.mcu=atmega328p
uno.build.f_cpu=16000000L
uno.build.core=arduino


As I read, the fastest is 115200 baud. That is for the UNO.  But what about the ATMEGA329P with bootloader chip sold online... What is the typical speed for those chip with the bootloader ?  Maybe it depend what board I select at the IDE level.

Nice to know...Anyway, thank retrolefty.

retrolefty

Quote
What is the typical speed for those chip with the bootloader ?  Maybe it depend what board I select at the IDE level.


Exactly. And if you purse through the various 328p board choices in the board.txt entries you will see that the baud rate used is different for diffent board types. Some of this is legacy values from older boards/bootloaders and of course if the board is using a 8 or 16Mhz clock value.

Now an up side to all this is that any 328p based board or standalone circuit that is running at 16Mhz can have the latest Uno bootloader burned into it and then enjoy the newest fasted upload speed, you will of course then need to select the board type as Uno even if it's an older model arduino board.

That make sense?

Lefty

Techone

Interesting... thank retrolefty.

Nice to know info.

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