Subject: Re: Xamiga24
To: amiga-Dev <amiga-Dev@NetBSD.ORG>
From: Markus Illenseer <>
List: amiga-dev
Date: 03/17/1995 12:20:22
mw wrote:
> If some people with '40 and RZ3 could look into RZ3SetHWCloc(): at the
> end of this function you'll find the following statements:
>         *(acm + (ACM_CURSOR_POSITION+0)) = x & 0xff;
>         *(acm + (ACM_CURSOR_POSITION+1)) = x >> 8;
>         *(acm + (ACM_CURSOR_POSITION+2)) = y & 0xff;
>         *(acm + (ACM_CURSOR_POSITION+3)) = y >> 8;
> now... if ANYONE has an idea why the above statements work for '30ies,
> but will just plain skip the third statement on a '40, *please* tell me...

 Looks like the problem I encountered with the Picasso and 040 in A2000.

 That RZ3SetHWCloc() is in grf_rh.c ?  And acm is a register on the Retina?
If so, please try to add (as stupid as this might be!) small delay
function, such as adding 10 NOPs or a small while(;;)-loop (both as
inline-functions to suppress de-optimisation).

 The other idea which comes to mind is that this register is probably
8Bit-only and the 040-interface in some machines will not access the
register correctly.

Markus Illenseer