Re: Trouble with freeMinT 1.15.0

[Michael Schwingen <rincewind@tubul.dascon.de>]

On Fri, Nov 27, 1998 at 05:20:39PM +0100, Konrad Kokoszkiewicz wrote:
> Well, my first guess was that there are pipeline problems and I of course
> know the function of NOP (it flushes the *read* pipeline on 68030).

The existence of the write pipeline in the 04 seems to be a lesser known fact
- I have seen lots of programs which do a write to 8.w and then try to
access some hardware register - and get a bus error, because the new bus
error vector is still 'pending' in the write pipeline.

> However, Frank told me about something that I consider strange, thus would
> be glad to verify that. Namely, the GEMDOS timer handler routine is
> supposed to make problems if it is ended by:
> 
> 	move.l	_old_timer,a0
> 	jmp	(a0)
> 
> and the whole thing works better if it is ended by:
> 
> 	move.l	_old_timer,-(sp)
> 	rts

Strange indeed. The TOS uses a0 itself for the same purpose (and saves *all*
registers - although I am not sure if this is documented and guaranteed),

cu
Michael
-- 
Michael Schwingen, Ahornstrasse 36, 52074 Aachen