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Re: [MiNT] Fix wrong size of outgoing packets in the FEC driver

on 9/5/14, 8:36 AM, Vincent Rivière wrote:

> On 04/09/2014 21:14, markus@mubf.de a wrote:
>> I have looked before into the TAS() macro, but didn't see anything
>> suspicuous - frankly, I didn't know tas is behaving bad on the Firebee.
>> The Coldfire manual doesn't say anything special about it (the text is
>> the same as for m68k processors), do you know more?
> Now I remember! That's a data cache issue.

This is a very interesting discussion about the TAS instruction. The GFA
Linker which is an extremely small program acts very strange on the FireBee.
I had no luck solving it the past several months. Now I find two TAS
instruction in there. Do you suppose this is the source of the mysterious
problems? Sometimes it works, sometimes not, much like a cache issue.

The first one is:

    tas (a1)
    bpl.s   label

The other one is:

    tas 0(a3,d1.l)
    bmi.s   label

Pierre Ton-That has been tolerating these problems with the linker, he ends
up having to re-compile a few times until it works. :(

Lonny Pursell    http://www.bright.net/~gfabasic/