Re: [stella] interrupts?

["Eric Ball/Markham/IBM" <eball@xxxxxxxxxx>]

Also consider that an interrupt automatically pushes the PC & PSR on the
stack and you only have 128 bytes of RAM.





                                                                                                                                        
                      "Eckhard                                                                                                          
                      Stolberg"                To:       <stella@xxxxxxxxxxx>                                                           
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> When (if ever) do we get an interrupt?  Is it possible to have the
> timer reaching zero to cause an interrupt?  Or must it be polled?

The 6507 processor has the interrupt pin removed to save costs.
Therefore it isn't possible to trigger an interrupt on the VCS.
The timer could generate an interrupt, but the processer won't
be able to sense it. You'll have to poll the timer, I'm afraid.


Ciao, Eckhard Stolberg


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