Table
G-1.
PET
Memory Map
(Rev
2
ROMs)
(Continued)
Memory Address
Sample Value
Description
Decimal
Hexadecimal Decimal Hexadecimal
RAM Subroutines
194-199
00C2-00C7 230
E6
Routine to letch next BASIC character
200
OOCS
173 AD
Entry to reletch current character
201-202 00C9-00CA 1929 0789
Pointer to source text
203-223
OOCB-OODF
201
C9
Work
area
lor
RND
lunction
OS
Page Zero Storage
224-225
OOEO-OOEl
33728
83CO
Pointer to start
01
line where cursor
is
Ilashing
226 00E2
0
00
Column position where cursor
is
f1ash-
ing (0-79)
227-228 00E3-00E4 33792 8400
Utility
pointer
229-230
00E5-00E6
1929
0789
End
01
current program
231-233
00E7-00E9
254
FE
Utility
234
OOEA
0 00
Fla9
lor
quote mode.
O=not
quote mode
235-237
OOEB-OOED
192
CO
Utility
238
OOEE
0 00
No.
01
characters
in
current
lile
na
me
239
OOEF
5 05
Current logical lile number
240
OOFO
255
FF
GPIB
primary address
241
OOFl
63
3F
GPIB
device number
242 00F2
39 27
Max.
no.
01
characters
on
current line
(39.79)
243-244
00F3-00F4
634
027A
Pointer to start
01
current tape buffer
(634 or 826)
245
00F5
23
17
Line number where cursar
is
Ilashing
(0-24)
246
00F6 10
OA
lia
storage
247-248
00F7-00F8
1024
0400
OS
pointer to program
249-250
00F9-00FA 3100
OC1C
Pointer
to
current
lile
name
251
OOFB
0
00
Number
01
Insert keys pushed to
go
252
OOFC
9
09 Seriai bit shift word
253
OOFD
0
00
Number
01
blocks
remalning
to
read/write
254
OOFE
0
09 Seriai ward buller
255
OOFF
243
F3
Overflow byte
lor
binary
to
ASCII
con-
verSions
Page
1 (256-5111
256-up
0100-up
32
20
Tape
read
working storage
(up
to 511)
and conversion stg.
256-318
For
errar correction in tape
reads
(62
bytes)
256-266 Binary to ASCII conversion
(11
bytes)
511-down
01
FF-down
0
00
Stack (down to 256)
Page
2-3 (512-1023)
OS
Working Storage
512-514 0200-0202 3801352 3A0108
24-hour clock incremented every
1/60
second (jiffy).
Resets
every 5.184.000
jiffies (24 hours). Stored
in
low to
high order.
416
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