Atari 400 Technical Reference Manual page 165

Appendix A -- CIa COMMAND BYTE VALUES
The following hex values are known to be legitimate CIa commands.
Most handlers:
03 OPEN
05 GET RECORD
07 GET CHARACTERS
09 PUT RECORD
08 PUT CHARACTERS
OC CLOSE
OD GET STATUS
Display Handler only:
11 --
FILL
12 -- DRAW
Diskette File Manager only:
20 RENAME
21 DELETE
22
FORMAT
23 LOCK
24 UNLOCK
25 POINT
26 NOTE
OPERATING SYSTEM C016555 -- Appendix A
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