Re: [Amforth-devel] Assembler - initial issues or bug

[Kalus M. <mic...@on...>]

Am 09.09.2010 um 20:10 schrieb Matthias Trute:
...
> There is no way to use forth words from within the
> assembler code. For that you need to initialize
> a forth vm and call it. The only "guide" for that
> is the startup code itself (amforth.asm).

and goes like this:

<snip>
    sei ; global interupt enable.
    push XL
    push XH
    lds  XL,0x5F   ; status register
    push XL
	.. maybe you have to include even more registers
    push R22       ; tosl = r22
    push R23       ; tosh = r23
    push R24       ; wl
    push R25       ; wh
    push YL
    push YH
    push ZL
    push ZH
	...
	<your code>
	...
; switch to high level forth: :
    sei
    ldi  XL,low(pfa_forthISR)
    ldi  XH,high(pfa_forthISR)
    jmp  DO_NEXT
; -- pointer to NEXT word:
pfa_forthISR:
    .dw  XT_MAINWORD
; -- come back to code:
    .dw  PC+1  ; next IP
    .dw  PC+1  ; next cfa
	...
	<more of your code>
	...
    pop ZH
    pop ZL
    pop YH
    pop YL
    pop R25
    pop R24
    pop R23
    pop R22
	.. maybe you have to include even more registers
    pop XL
    sts 0x5F,XL
    pop XH
    pop XL
    jmp  DO_NEXT (or RTI if you are in an ISR)
</snip>

see examples in paper VD1/2010  http://www.forth-ev.de/filemgmt/ 
viewcat.php?cid=53

worked with amforth3.6
still good with 4.1?
Michael