Table G-l.
PET
Memory Map
(Rev
2
ROMs)
(Continued)
Memory Address
Sample Value
Description
Decimal Hexadecimal Decimal Hexadecimal
57344-59391
EOOO-E7FF
Screen Editor
Starting Address
Function
57416 E048 ATN
57525 E085 Initialize 8ASIC
system
57910 E236 Clear screen
57981
EnD
Character letch
58004-58986 E294-E66A
Video driver
58282 E3AA
Scroll processor
58346
E3EA
Video display routine
58185
E349
Ouote mode I$EA)
switcher
58346
E3EA
Print character
58713 E559 Scroll 1 line
58758 E586
Interrupt Request
(lROI
58987-59012 E668-E684
Interrupt handler
59013-59198
E685-E73E Clock update
59199-59227 E73F-E758 Keyboard scan
59228-59348 E75C-E7D4 Keyboard encoding table
Page
233-240 1/0 Ports
and
Expansion 1/0 IPIA's and VIAl 159392-614391
Keyboard PIA
(59408-69411)
59408 E810
233
E9
1/0
Port A and Data Direction register
59409
E811
60
3C
Control Register A - screen blanking
52=Screen
off Iblanked)
60=Screen
on
59410
E812
255
FF
1/0
Port 8 and Data Direction register
255=all
keys except:
254=RVS
key
253=key
251=SPACE key
247=
< key
59411
E813
61
3D
Control Register 8 -
*1 cassette motor
53=motor
on
61
=motor
off
IEEE
Port PIA
(69424-69427)
59424 E820
255
FF
1/0
Port A and Data Direction register
PEEK
(59424) reads input data.
59425
E821
188
8C
Control Register A - set output line CA2
POKE
59425.52=low
POKE
59425.60=high
59426
E822
255
FF
1/0
Port 8 and Data Direction register
POKE
59426,data writes output data
POKE
59426.255 belore a read ta Port A
59427
E823
60
3C
Control Register 8 - set output line C82
POKE
59427.52=low
POKE
59427.60=high
422
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