[Amforth-devel] How to compile amforth with recent avra

[Marcin C. <sa...@sa...>]

Hello, as the FreeBSD user I decided to give avra a try. 
It was necessary to add some patches to the assembler and
one dubious change to amforth, but it works very well,
and even .hex files are the same when produced by avra
and the Atmel tool.

I have posted patches to the newest avra (trunk, they might
work with 1.3.0 release) on Sourceforge:

3044547         Error:: ldi can only use a high register (r16 - r31)
                 https://sourceforge.net/tracker/?func=detail&aid=3044547&group_id=55499&atid=477233

3044545         movw y, z causes Error:: No register associated with y and z
                 https://sourceforge.net/tracker/?func=detail&aid=3044545&group_id=55499&atid=477233

3044541         .ifndef does not work (Can't redefine constant, use .SET)
                 https://sourceforge.net/tracker/?func=detail&aid=3044541&group_id=55499&atid=477233

As per suggestion I am using Atmel include files taked from the latest
AVR Studio (I place them in /usr/local/libdata/avra and modify avr-build.xml
accordingly).

The only (trivial) issue left is that avra checks all code ranges
produced by the assembler and complains if overlap occurs.
Atmel assembler does not care and happily produces two lines
in HEX file for the same range.

This happens when the serial rx or tx via IRQ is enabled,
core/devices/atmega328p/device.asm produces:

.org $024
          rcall isr ; USART Rx Complete
.org $026
          rcall isr ; USART, Data Register Empty

and core/drivers/usart-isr-[rt]x.asm produce:

.org URXCaddr (or .org UDREaddr)
   jmp_ usart_rx_isr

I have enclosed a silly patch (irq.patch) that encloses them
info .ifdefs to avoid producing overlapping assembly.
I am not sure this is the right way to handle it, though.

Enclosed please find also patches to solve flash size
exceeded problem when producing .hex files for arduino.

One question by the way: At amforth_interpreter (0x3800 in case of
328p) we start the inner interpreter (label DO_DODOES).

Wouldn't that make sense to to have an additional "jmp_ amforthstart"
there as well? This would probably allow booting Amforth independent
of the BOOTRST fuse setting.

And finally, there is a patch attached for ant files to 
call avra. I am flashing one Arduino board (ATmega 328p 
Duemilanove) with another one (ATmega168 Freeduino) via
In-circuit Serial Programming.

--Marcin