Table G-1.
PET
Memory
Map
(Rev
2 ROMs) (Continued)
Mamory
Addrass
Sample Value
Decimal
Hexadecimal
Decimal
Hexadecimal
Description
3
a
a
a
a
a
a
a
a
a
a
00
Delault
input
device
number
(O=keyboardl
03
Delault
output
device
number
(3=screenl
00 Tape parity byte
00
110
utillty
00 110
utility
00 Byte pointer in lilename transler
00
110
utility
FF
110
utility
00 110
utility
08 Seriai
bit
cou
nt
00 Count
01
redundant tape blocks
00 Tape
utility
00 Cycle counter
Ilip
lor
each bit read Irom
tape
00 Countdown synchronization
on
tape
write
00 Tape buffer 1 index
to
next character
00 Tape buffer 2 index to next character
00 Countdown synchronization
on
tape
read
00 Flag to indicate
bit/byte
tape error
00
Flag
to
indicate tape error
O=lirst
hall-byte marker not written
00 Flag to indicate tape error
0=2nd
hall-byte marker not written
ITape
dropout counter
00 Tape dropout counter
80 Flag
lor
tape
read
current lunctlon
09 Checksum
utility
01
Tape buffer
lor
cassette * 1 (192 bytes)
AD Tape buffer
lor
cassette
*2
(192 bytesl
1C
Utility
space lunused.
Page
4-32 (1024-8191)
00
1User program
area
Page
33-128 18192-327671
00
1Expansion RAM
Page
129-144 132768-368631
12
OC
TV
RAM
32768-33767 Display memory
(1000 bytesl
Page
145-1
92
(36864-491
51)
a 00 1Expansion
ROM
Page
193-232
BASIC
(49152-593911
a
a
a
a
a
255
a
8
a
a
a
a
128
9
1
173
28
2000-7FFF
8000-8FFF
0276
0400-1FFF
0274
0275
0265
0266
0267
0268
0269
026A
0268
026C
026D
026E
026F
01B3
0271
0272
0273
0264
0270
9000-BFFF
0277
0278
0279
027A-0339
033A-03F9
03FA-03FF
625
626
627
1024-8191
624
628
629
612
8192-32767
630
611
613
614
615
616
617
618
619
620
621
622
623
36864-49151
32768-36863
631
632
633
634-825
"=- 826-1017
1018-1023
49152-49153
49154-49155
49156-49157
COOO-COOl
C002-C003
C004-C005
50973
50760
52277
C710
C648
CC35
Pointers
to
BASIC Routines
POinter
-1
to END'
Pointer
-1
to
FOR
Pointer
-1
to
NEXT
These memory locations contain the address
of
the byte preceding the specified BASIC routines
418
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