ATmega88 & 8MHz internal osc. won't respond to Arduino

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Tweak the Make file atmega88 entry to lower the clock speed to 8Mhz
2. omake atmega88
3. use AVRDUDE to set fuses to Lilypad 8Mhz standard: DD,E2,04 (same family, 
same result as atmega168)
4. Board LED blinks as expected, but never connects to bootloader (blink 
iterations can be changed, and are correctly displayed)

What is the expected output? What do you see instead?
AVRDUDE in Arduino IDE times out after resetting the board

What version of the product are you using? On what operating system?
Win XP, custom board

Please provide any additional information below.
It -could- be an issue with the ATmega88PA, which was the one tested. (and 
readily availabe these days!)

A Japanese deveoper created an original (huge, 2k) bootloader for the 88 family 
at 8Mhz intosc, but there are distinct variants for the 88 and 88P.  The 88P 
version works fine, although the upload speed is 19,200 (not sure it that was a 
requirement...)

I have a version of Optiboot for the ATmega88 using 16Mhz xtal osc which works 
fine, so it's probably related to the internal osc.

Original issue reported on code.google.com by awebu...@hotmail.com on 20 Oct 2011 at 12:43

[GoogleCodeExporter]

It seems like most 8Mhz internal oscillator bootloaders use 19,200 baud.  Is 
115,200 baud a practical speed for the internal oscillator at 8MHz?

Does the Optiboot "lilypad_resonator" setting actually work?  ;)

Also, setting the "-DBAUD_RATE" to anything below 57,600 causes the make to 
fail.  Can this be corrected?

Original comment by awebu...@hotmail.com on 20 Oct 2011 at 1:12

[GoogleCodeExporter]

115200 has quite a high error at 8MHz.
Here's a diff for supporting lower bit rates.  Can you test it? I'm not really 
sure what the old code was trying to do.

Original comment by wes...@gmail.com on 30 Oct 2011 at 9:19

Attachments:

• optiboot_brg.diff