switching between EPROMS

[Thor Johnson]

On Wed, 28 Aug 1996, Warren Crowther wrote:

> >     If you switch it with the engine turned OFF, I don't think you'd have 
> >     a problem.
> 
> This is a simple solution, and will work, but..
> 
> I'd prefer to do it with the engine ON!!!  I don't see any reason why it
> cannot be done, provided the switch over is not done at a critical time, and
> that the only difference between the EPROMS is the data: ie. the fuelling,
> ignition timing, etc.  Also it should be done quick enough so that the micro
> does not miss an external data fetch (anyone know what the micro will do in
> this case??  will it hang or retry? ).

  If you switch when the uP is not reading or writing (look at uP docs), 
AND the uP doesn't copy the tables into another RAM chip (for speed..?), 
there shouldn't be any problems.

                Thor Johnson
       johnsont at falcon.mercer.peachnet.edu
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