Go Down

Topic: Arduino ATmega1284p bootloader (Read 8 times) previous topic - next topic


The programmer is set for 5V?

You didn't say how you were able to install the bootloader.
I install it via the the IDE, Tools:Burn Bootloader.
This ensures that the fuses are all set correctly for 16 MHz crytsal operation.
I download sketches after that.
If the fuses are not set correctly, the data rate for serial downloads will be mismatched and the download will not work.
Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.


Jan 10, 2013, 08:40 pm Last Edit: Jan 10, 2013, 08:43 pm by oric_dan(333) Reason: 1
I selected the Mighty 1284p, 16MHz using Optiboot as board and Arduino as ISP as programmer.

This is wrong for downloading general sketches, it's only used to download the ISP sketch into
the 1284P to use it to program other chips.

Secondly, as Bob asked, how did you burn the bootloader into the 1284P chip in the first place?
Are you sure that went correctly?

Thirdly, your FTDI cable looks like a knockoff of the FTDI friend. It may or may not "in
fact" be using DTR, rather than RTS. If it's actually using RTS you need to go to the
Control Panel device manager for the COMPORT and select "set RTS on close".

Fourthly, it looks like in your 2.8MB picture you have TX and RX wired wrong. The TX
and RX labels on the FTDI Friend and regular FTDI cables specify the signal flow with
respect to the cable, not the Arduino. So, the wires have to be swapped between the
2 devices. BTW, I always insert 1K series-Rs in the RX,TX lines in case I hook them
up backwards.

The other thing is I use the FTDI Friend and FTDI cables most of the time, and have
never tied CTS to anything.


Thanks for the great answers!

I changed the setting in the device manager, just in case to test it. I used this tutorial: http://www.gammon.com.au/forum/?id=11637 and the Serial Monitor said that it was successful. That do I have to choose to download a general sketch?

Yes it is a cheap FTDI version, on the ebay page they said it uses DTR. Thanks for the information that I have to swap TX and RX. Is connection via the cap to the reset pin right for DTR?


Jan 10, 2013, 08:59 pm Last Edit: Jan 10, 2013, 09:00 pm by oric_dan(333) Reason: 1
For a general sketch, you just go to your sketchbook or the IDE "File > Examples",
and choose something other than ArduinoISP.

I think your reset pin wiring is ok. All you need is a 0.1 uF cap from FTDI DTR to the
1284P reset pin, plus a 10K pullup to 5V on the reset pin. Simple.

I am still curious [Bob too], as to how you burned the bootloader into the 1284P in the
first place. ???


Yes I am, how was the bootloader set up?

I use an Atmel AVR ISP MKii.  I use the IDE to burn the bootloader first to make the fuses are set correctly.
The times I forgot to that, I spend a frustrating 1/2 figuring what is going on, eventually figuring out the clock is really slow, and then finally remembering to do the bootloader for the fuses.  Getting better about that.

I then use File: Upload Using Programmer with the MKii if I don't need the bootloader, or I connect up an FTDI Basic for downloading sketch via serial interface.

I don't use the Optiboot 16 MHz tho, I always use Bobuino so Serial is at D0/D1, SPI is D10-11-12-13, and I2C is A4/A5 of D18/D19, just like on a '328 board.  I like a little consistency.
Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

Go Up