Apple Apple-1 - Page 9

6502
HEX
MONITOR
LISTING (continued)
FFEB
90
02
FFED
69
06
FFEF
2C 12 D0
E
FFF2
30
FB
FFF4
8D 12 D0
FFF7
60
FFF8
00 00
(unused)
FFFA
00
0F (NMI)
FFFC
00
FF
(RESET)
FFFE
00 00
(IRQ)
ECHO
BCC
ECHO
ADC
#$06
BIT
DSP
BMI
ECHO
STA DSP
RTS
Yes, output it.
Add
offset for letter.
DA bit (B7)
cleared
yet?
No, wait
for display.
Output
character.
Sets
DA.
Return.
HARDWARE
NOTES
Page
Variables
XAML
24
XAMH
25
STL
26
STH
27
L
28
H
29
YSAV
2A
MODE
2B
Other Variables
IN
200-2
KBD
D010
KBD
CR
D011
DSP
D012
DSP
CR
D013
PIA
KBD/DSP
Interface
Bl
B2
KBD
B3
\SCII
i
B4
Data B5
B6
B7
+5
KBD
STROBE
Reset
PA0 D0-D7
PA1
RS0
±
PA2
PA
3
PA4
PA5
PA6
PA7
RES
RSI
CS0
CS1
CS2
E
Vc
Vss
CA1 R/W
CB1
CB2
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
^DATA BUS
-
A0
-
Al
-
A4
+
Decode
A15, A14,
A13, A12
to
$DXXX
02
+5
•R/W
i>
B6
B5
-*B4
B3
B2
Bl
B0
PIA
6820
One Shot
(3.5
usee)
RDA (UART style)
(from display)
DA
(UART style)
(to
display)
ASCII
to
display
-7-