Re: Reset code location?

["Don" <numberfiveplusone@gmail.com>]

"Jayson Smith" <ihatespamratguynospamplease@insightbb.spamsucks.com> wrote 
in message qridnaceu7a1C_DWnZ2dnUVZ_gednZ2d@insightbb.com">news:qridnaceu7a1C_DWnZ2dnUVZ_gednZ2d@insightbb.com...
> Here's a silly question. Where is the code on an Apple that runs the 
> instant you hit Reset or switch the power on. Or is there some special 
> code not anywhere in accessible ROM or something? In other words, if a 
> program wanted to trigger the series of events that goes with hitting 
> Reset, E.G. beep, check the power-on byte, go through the reset vector if 
> valid, otherwise scan for a disk controller and boot, could it do it, and 
> how would it go about doing this?
> Thanks.
>
>
IIRC the 6502 jumps to the address specified by locations FFFC-FFFD when the 
RESET line is asserted.  If you check that location (it's in ROM) you should 
find the address of the Apple reset routine.  [BTW: FFFE-FFFF is the IRQ 
vector and FFFA-FFFB s the NMI (Non-Maskable Interrupt) vector.]
-- 
be seeing you ... Don
Don Melton, Sr. Consultant, Vatic Technologies Limited