bootloader for atmega 2561

Can you help me with burninig atmega2561?
I have replace board.txt: My 2561



pins_arduino file and put new bootloader for 2561.

But when I avrdu-ing it says
avrdude: initialization failed, rc=-1
avrdude: AVR device initialized and ready to accept instructions
avrdude: Device signature = 0x000000
avrdude: Yikes! Invalid device signature.

I have double checked wiring on board but nothing found.
Could you give me advise what can I do else?

Initial bootloading on a new part requires a slower speed.
Like, 25% of the speed of a part that has a bootloader already.

Doesn't look like the part is talking. Are you sure the programmer is connected to +5, Gnd, Reset, SCK, MISO, MOSI? The part has 10K pullup to +5 on its Reset pin? There are 0.1uF caps on the VCC and AVCC pins?
They may be, it's just hard to tell on that picture.

I'll check all of it tomorrow! Thank you a lot!

This is my current circuit (wrong!!!) see below right circuit
Please help me with your suggestion

Need to see/know component values.

R1 10K
C1&C2 22 pF
Other C 0.1 mkF

Do you have any suggestions?
The circuit still never works....

Try this - burn the bootloader like it was a 2560, and then don't use the ports you don't have.
Make boards.txt entry look like the 2560 entry, and copy the 2560 section of avrdude.conf into a 2561 section and put the correct signature bytes for the 2561 in.

If that works, you'll know your electronics are good, then you can go back to messing with UART1 vs UART0 for serial downloads.

Bingo! I have done!
For ISP (MISO/MOSI) on this package(64-pin) Atmel uses other pins.
See attachment and check manual

So the initial schematic chip symbol is not correct? That's aggravating!
Glad you got it worked out.

This is correct circuit for Atmega 2561 in 64-pin package:

But this is not the end of my journey…
I have recieved error when I try to write bootloader.
I try both case 2560 and 2561 without success.

Where I could get right bootloader for 2561?


It is going but at the end - verification error.
What can I do?

I would like notice that bootloader works!
Yes verification error but bootloader works and I am able to load simple sketch.

section in board.txt: Mega 2561



bootloader and pins_arduino.h in attachment

To all Thank you a lot!

pins_arduino.h (11.5 KB)

change bootloader extention to hex

stk500boot_v2_m2561_16mhz.hex.txt (21.3 KB)