Can't get DHT22 working with MySbootloader

[tekka]

@fifipil909 sounds like a frequency mismatch. What board and settings are you using for standard upload and to generate the .hex file?

[fifipil909]

with the default bootloader I use : Arduino pro mini 3.3V - 8Mhz

For the MYSbootloader I use :

proMYSBL.name=ATmega328 16Mhz MYSBootloader
proMYSBL.upload.tool=avrdude
proMYSBL.upload.protocol=arduino
proMYSBL.upload.maximum_size=30720
proMYSBL.upload.maximum_data_size=2048
proMYSBL.upload.speed=115200
proMYSBL.bootloader.tool=avrdude
proMYSBL.bootloader.low_fuses=0xF7
proMYSBL.bootloader.high_fuses=0xDA
proMYSBL.bootloader.extended_fuses=0x06
proMYSBL.bootloader.unlock_bits=0x3F
proMYSBL.bootloader.lock_bits=0x0F
proMYSBL.bootloader.file=MySensors/MYSBootloader.hex
proMYSBL.build.mcu=atmega328p
proMYSBL.build.f_cpu=16000000L
proMYSBL.build.board=AVR_UNO
proMYSBL.build.core=arduino
proMYSBL.build.variant=standard

I try to change the f_cpu settings to 8000000L but same result.

[tekka]

@fifipil909 8mhz crystal on your board, 3v3? Did you change f_cpu for compiling or for flashing?

[fifipil909]

Yes i'm using the 8mhz external oscilator.

I just change f_cpu while flashing the bootloader.
Didn't try yet to recompile.

[fifipil909]

I confirm it was due to Clock mismatch.
I burnt a 8mhz version of the bootloader, assign good fuse.

and now get everything working.

Thanks

[tekka]

@fifipil909 said:

I confirm it was due to Clock mismatch.
I burnt a 8mhz version of the bootloader, assign good fuse.

and now get everything working.

Thanks

Importantly, it's not the bootloader at 8mhz that fixed the issue, it's the correct fuse settings matching f_cpu and the crystal. The bootloader is not controlling anything but OTA FW update.

[carlierd]

Hello,

I have an issue really close to yours. I burnt MYSBootloader to an Arduino Pro Mini at 8MHz and 3.3v.
Burning is ok and using Nick Gammon sketch I confirm it's correct:

Atmega fuse calculator.
Written by Nick Gammon.
Version 1.10
Compiled on Nov 21 2015 at 10:56:15 with Arduino IDE 10605.
Attempting to enter programming mode ...
Entered programming mode OK.
Signature = 0x1E 0x95 0x0F 
Processor = ATmega328P
Flash memory size = 32768
LFuse = 0xF7 
HFuse = 0xDA 
EFuse = 0xFE 
Lock byte = 0xCF 
Clock calibration = 0xA8 
External Reset Disable.................. [ ]
Debug Wire Enable....................... [ ]
Enable Serial (ICSP) Programming........ [X]
Watchdog Timer Always On................ [ ]
Preserve EEPROM through chip erase...... [ ]
Boot into bootloader.................... [X]
Divide clock by 8....................... [ ]
Clock output............................ [ ]
Bootloader size: 2048 bytes.
Start-up time: SUT0: [ ]  SUT1: [ ] (see datasheet)
Clock source: full-swing crystal.
Brownout detection at: 1.8V.

But impossible to upload a sketch after that. I got the 'not in sync' problem:

avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding

@tekka: I understood from your last reply that I need to change fuse settings for matching f_cpu and the crystal ? I only change f_cpu to 8000000L in board.txt but without fuses modification and no bootloader compilation. Can you confirm modifications I have to do ?

Thanks !

[tekka]

@carlierd With MYSBootloader you cannot upload a sketch the conventional way, i.e. you cannot upload via a serial connection. MYSBootloader is OTA upload only.

[carlierd]

Oups !! Shame on me :joy:

It's also working using RFM69 ?

[tekka]

@carlierd no, not implemented (at the moment)

[carlierd]

One more question (or perhaps no ;) ) signing is working without MYSBootloader ?

Thanks a lot for your replies.

David.