[Amforth-devel] Atmega8 UART issues

[Klaus Z. <kl...@ze...>]

Hi,
i probably got into the same problems like Matt Eastburn.

I also used AVStudio 4.13 to compile & link and burned the HEX and EEP 
files with AVR Prog 1.4 into an Atmega8L with an external Xtal with 
36864 Mhz.

I fused for Highsped external Xtal and 2.7V BOD, leaving all other fuses 
alone.
@Matt: click on the "Advanced settings button" in AVR prog to access the 
fuses.

Like for Matt the resulting controller did not communicate via USART. 
Reducing the baudrate didn't help. So I added some Assembler code for 
trace output and that worked. I could follow the inner interpreter and 
found this running all the time, but seemed not reaching the 
"applturnkey" ever.

Finally I stopped this and used an ATmega168 instead. After correcting a 
Typo in "atmega168.asm" (The label ADCCaddr was written as ADCaddr) that 
compiled and linked fine and after burning that output amforth started 
without a problem.

So maybe something is wrong in "atmega8.asm" when using the Atmega8L ?

@developers: Keep up your great work!
I've not used Forth since 1986 on Z80 and 8088- systems but remember how 
much fun that was.
Now its even greater being able to explore those cool microcontrollers 
in direct interaction !

@Matt: If possible, try also another controller since Atmega8 ist a 
little bit small for amforth anyway. There are only 17% memory free for 
your applications. Atmega168 is pincompatible but has 16kb instead 8kb 
FlashROM and a built-in far-distance JMP-instruction too ;)

Kind regards

Klaus Zerbe