Table 6-2.
PET
Memory
Map
(Rev.
3 ROMs) (Continued)
Memory Address
Semple Value
Description
Decimal
Hexadecimal
Decimal
Hexadecimal
216
0008
24
18
Line number where cursor is flashing
10-241
217
0009
10
OA
1/0 storage: last
key
input. buffer
checksum. bit buffer
218-219
OODA-OODB
0
0000
Pointer to current file name
220
OODC
0
00
Number of Insert keys pushed to 90
221
0000
0
00
Seriai bit shift word
222
OODE
0
00
Number
of
blocks remammg to
read/write
223
OODF
0
00
Seriai word buffer
224-248
00EO-00F8
High byte of screen Ime addresses
128
80
224-230~128
lIines
1-7)
129
81
231-236~129
lIines 8-13)
130
82
237-243~130
lIines 14-20)
131
83
244-248~131
limes 21-25)
249
00F9
0
00 Cassette * 1 status switch
250
OOFA
0
00 Cassette
*2
status switch
251-252
OOFB-OOFC
54144
0380
Tape start address
253-255
OOFD-OOFF
243
F3
Utllity
Page
1
(256-511)
256-up
0100-up
32
20 Tape read working storage
(up
to
5111
and
conversion storage
256-318
For
errar correction
in
tape reads
(62
bytesl
256-266 Binary to ASCII
conversIOn
III
bytesl
511-down
01FF-down
44
2C
Stack (down to
2561
Page
2-3 (512-1023)
512-592
0200-0250
BASIC
input Ime buffer
180
bytes)
12597
3135
512-513
0200-0201 Program Counter
50
32
514
0202 Processor status
0
00
515
0203 Accumulator
171
AB
516 0204 X index
0 00
517
0205 Y index
0 00
518 0206 Stack pointer
15104 3800 519-520
0207-0208 User modifiable
IRQ
593-602 0251-025A
4 04
Table of loglcal numbers of open files
603-612
025B-0264
4
04
Table of device numbers of open files
613-622 0265-026E
255
FF
Table of secondary address modes of open
files
623-632
026F-0278
3 03 Keyboard buffer
110
bytes)
633
0279
28
lC
Keyboard
utility
634-825
027A-0339
28
lC
Tape buffer for cassette
*1
(192 bytes)
826-1017 033A-03F9
173 AD
Tape buffer for cassette
*2
(192 bytes)
1018-1019
03FA-03FB
59383
E7F7
Vector for Machine Language Monitor
1020-1023
03FC-03FF
195
C3
Utility
space/unused
338
To Next Page
Loading...
