1Mhz

I've just build a project running from 3 AA batteries, using shut_down sleep modes to cut power. first i had it running on the lilypad 8Mhz bootloader, but later i switched a fuse in avrstudio to let it run on 1Mhz. but now the bootloader won't work, expecting it to be running on 8Mhz. then i thought about making another board entry in the arduino IDE and copied the lilypad folder in the hardware/bootloaders folder with the non inspiring name batDuino.

then i edited the makefile in the src directory

# enter the target CPU frequency
AVR_FREQ   = 1000000L

# enter the parameters for the avrdude isp tool
ISPTOOL         = stk500v2
ISPPORT         = usb
ISPSPEED   = -b 115200

but, running on 1Mhz, can the atmega cope with the 115200 baudrate and if not, does the IDE listen to the ISPSPEED var here so i can set a slower speed?

and to conclude this questionare, how would i make a hex file out of it, be it on mac osx or avrstudio on pc?

Am i on the right track here?

Oh yeah,

i've made a extra entry in the hardware/boards.txt file:

##############################################################

batduino.name=Batteries Arduino

batduino.upload.protocol=stk500
batduino.upload.maximum_size=14336
batduino.upload.speed=19200

batduino.bootloader.low_fuses=0xe2
batduino.bootloader.high_fuses=0xdd
batduino.bootloader.extended_fuses=0x00
batduino.bootloader.path=batduino
batduino.bootloader.file=BatDuinoBOOT_168.hex
batduino.bootloader.unlock_bits=0x3F
batduino.bootloader.lock_bits=0x0F

batduino.build.mcu=atmega168
batduino.build.f_cpu=1000000L
batduino.build.core=arduino

it looks as if i could just set the batduino.upload.speed to 2400 and use the lilypad bootloader. maybe that is easier than making yet another bootloader as mentioned above. or would the delay() issue arise then?

any thoughts on this?

There is probably a simple answer to this, but why don't you just burn the lilypad bootloader?

I did, but the lilypad is running on 8Mhz, and i want more powersavings by running on 1Mhz. fun is, in 2006 I participated in a discussion of the same subject in this forum, but i completely forgot about it. someone else came up with it lately. the discussion is here:

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1163418637

I suggest to continue the discussion there.