Atari 8-Bit Computers: Revisions of OS, BASIC and CTIA/GTIA
GTIA or CTIA?
In early 1982, Atari began upgrading ist computer models 400 and 800 by using the newer GTIA graphics chip instead of the older CTIA. Execute the following BASIC program:
10 GRAPHICS 9
20 GOTO 10
If the screen turns blue, your computer has an CTIA chip. If it turns black, that you have an GTIA.
| Screen Colour |
Graphics Chip Version |
| blue |
CTIA |
| black |
GTIA |
Table 1: Screen colour indicates CTIA/GTIA
OS Revision A or B?
In January 1982, revision B of the operating system was released. Execute the following BASIC statement to check content of memory at location $E404 (58383):
PRINT PEEK(58383)
| Memory Content |
OS Revision |
| $38 (56) |
A |
| $00 (0) |
B |
Table 2: Memory content indicates OS revision
BASIC Revision A, B or C?
Execute the following BASIC statement to check content of memory at location $A8E2 (43234):
PRINT PEEK(43234)
| Memory Content |
BASIC Revision |
| $A2 (162) |
A |
| $60 (96) |
B |
| $EA (234) |
C |
Table 3: Memory content indicates BASIC revision
Related Sites
Memo Pad - www.geocities.com/SiliconValley/Vista/3015/memopad.html
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this page was updated: 09.05.02 14:20:52
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