"Richard Lang" <[EMAIL PROTECTED]> wrote:
> On one Palm III the application crashed whenever a "tas offset(a3)" opcode
> was encountered. It worked fined on the Palm III emulator and on our Palm
> IIIx. Problem now solved by re-coding to avoid this instruction.
>
> Is this a known problem with some Dragonball processors? or a one off?.
> Most importantly, are there any other assembly language instructions
> that should be avoided if the application is to run on all Palms.?
I've not looked at the hardware design of the various units, but I do
know that the TAS instruction uses a read-modify-write memory access
cycle, during which AS remains true, and the R/W line changes state
(along with the data strobes). The CPU-memory interface has to be
designed to accomodate this. (Something I overlooked in my first 68K
design :-)
--
Roger Chaplin
<[EMAIL PROTECTED]>
