At location VVBLKI (546,547), we discussed the various stages of VBLANK and I promised a list of things that were done during stage two. This is that list.

The following hardware registers are updated with the values in their shadow registers (listed in the order they are updated):

Shadow	Hardware
LPENV	PENV
LPENH	PENH
SDLSTH	DLISTH
SDLSTL	DLISTL
SDMCTL	DMACTL
GPRIOR	PRIOR
PCOLR0-3	COLPM0-3 (Colors are first adjusted for the
COLOR0-3	COLPF0-3 attract mode.)
COLOR4	COLBK
CHBAS	CHBASE
CHACT	CHACTL
STRIG0-3	TRIG0-3
PADDL0-7	POT0-7

The following shadow registers are updated with the values in the corresponding hardware registers:

Shadow	Hardware
STICK0,1	PORTA
STICK2,3	PORTB
PTRIG0-3	PORTA
PTRIG4-7	PORTB

In addition to all this, the following timers are decremented, and the appropriate actions taken if they reach zero:

CDTMV2-5

KEYDEL

SRTIMR

Note that the last two timers deal with the keyboard debounce and repeat, respectively, and are only decremented if necessary. CDTMV1 is taken care of in stage one.

Finally, the last thing stage two does is jump through VVBLKD (548,549).

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