Commodore PET User Manual page 356

Table 6-2. PET Memory Map (Rev. 3 ROMs) (Continued)
Memery AdtIre8. Sample Value
Description
Decimal Hexadecimal Decimal Hexadecimal
Screen Editor
Sterting Addr••• Function
57344-5391 EOOO-E7FF " 57384 E028
TAN
57484 E08C ATN
57593 EOF9 Subroutine ta be moved ta
page 0 ($70-$871
57617 Elll
Initial RND seed (5 bytes)
57622 E116 Initialize BASIC system
57897 E229 Clear screen
57943 E257 Home cursor
57989 E285 Character fetch
58100-58906
E2F4-E61A Video driver
58100 E2F4 Input fram screen
58175 E33F Ouate mode ($CDlswitcher
58188 E34C Print character
58687 E53F Serail 1 line
58907-59113 E61B-E6E9 Interrupt Handler
59114-59127 E6EA-E6F7 Keyboard Scan
59128-59241 E6F8-E769 Keyboard Encoding Table
59242-59391
E76A-E7FF Subroutines for Machine Language Monitor
Page 233-240 1/0 Ports and Expansion 1/0 IPIA's and VIA) 159392-61439)
Keyboard PIA (59408-59411)
59408
EB10
249
F9 1/0 Port A and Data Direction register
59409
E811
60
3C
Control Register A - screen blanking
52~Screen
off (blanked)
60-Screen on
1/0 Port B and Data Direction register
59410
E812
255
FF
255=all keys except:
254-RVS key
253=[ key
251 =SPACE key
247~< key
Control Reg isters B -
*'
1 cassette motor
59411
E813
61
3D
53=motor on
61=motor off
IEEE Port PIA (59424-59427}
59424 E820 255 FF 1/0 Port A and Data Direction register
PEEK (59424) reads input data
59425 E821 188
BC
Control Register A - set output line CA2
POKE
59425.52~low
POKE 59425.60=high
59426
E822
255
FF
1/0 Port B and Data Direction registers
POKE 59426. data writes output data
POKE 59426.255 before a read ta Port A
59427 E823 60 3C
Control Register B - set output line CB2
POKE 59427.'52-low
POKE 59427.60=high
343