Atari 400 Hardware Manual

fiTARl 800 CHECKERS DlSPLA'o' BV C SHR~I :J/3:1/SO
2720 ; MOVE COP'o'RlGHT 11ESSAIJE TO MESSAGE DlSPLA'o' LINE
;one
-:.,;~9( R21~
,;'(4~ u:, ;: .1 .. ~
'57 :!IE BC•E957 27'50 I N6
lDA COF'V, X
'57A1
900054 2760
STA
TITL.><
57A4 CA
2770
DEX
'57A~ 10F7
27S0
BPL
1N6
2790
2SOO ;LOOP TO MOVE BOAkD TO GRAPHICS AREA
2S10 ;THE CHECKERS f'ROC.f.'AM LOGIC COULD BE ADDED HERE OR A VBLANK INTERRUPT COULD BE USED .
2820
2830
LOOP
57A7 20AD57 2S40
JSR UPCHR
57AA 4CA757 2850
JMP
LOOP
2860
2870
2880
2890
2900 ;UPCHR --SUBROUTINE TO MOVE 32 BYTES OF CHECKER BOARD TO DISPLAY RAM .
2910 ;
2920 UPCHR
57AD A21F
2930
LOX
1131
;SQUARE 31 =UPPER LEFT
57AF A000
2940
LDV 110
2950 UPLP1
5781 A90J:
2960
LOA 114-1 ; 4 SQUARES/L 1 NE
5783 BD2B50 2970
STA
TO
2980 UPLP2
5786 BD0050 2990
LDA
BOARD, X
5789 992654 3000
STA 8ROSP+2,Y ;FOR ROWS SHIFTED TO RIGHT
H
578C 8DFC4F 3010
LOA BOARD-4,)(
<
578F 993454 3020
STA
8RDSP+f10,V ;FOR ROWS SHIFTED TO LEFT
57C2 C8
3030 INV
,_.
57C3 ca
3040 lNV
0
57C4 ca
3050 INV
57C5 CS
3060
lNV
57C6 CA
3070
DEX
57C7 CE2050 3080
DEC
TO
57CA 10EA
3090 8PL
UPLP2
3100
57CC 98
3'110
T','A
57CD :18
3:120 CLC
57CE 6910
3130 ADC
11$10
5700 AS
3140 TAV
5701 SA
3150 TXA
5702 E903
3160 SBC
114-1
;CARRV
IS CLEAR <SUBTRACT 4)
5704 AA
3170 TAX
'57C>5 BODA
:use 8CS
UPLP1
5707 60
3190
RTS
3200
3210
;
3220
3230
(
\.

Atari 400 Specifications

General

Manufacturer	Atari
Model	400
Type	Home Computer
Release Year	1979
CPU	MOS Technology 6502
CPU Speed	1.79 MHz
ROM	10 KB
Operating System	Atari OS
Keyboard	Membrane keyboard
RAM	8 KB (expandable to 48 KB)
Graphics	ANTIC and GTIA chips
Sound	4 channels
Display	RF output for connection to TV
Storage	Optional cassette tape drive or floppy disk drive
Ports	Cartridge
Display Resolution	320x192 (16 colors)