CIOINT
58534         E4A6

CIO's initialization routine.

CIO
58564         E4C4

The main CIO routine (includes the following routines).

CIOPEN
58633         E509

OPEN routine.

CICLOS
58675         E533

CLOSE routine.

CISTSP
58702         E54E

STATUS and special requests routine.

CIREAD
58729         E569

GET routine (GET character and GET record).

CIWRIT
58825         E5C9

PUT routine (PUT character and PUT record).

CIRTN1
58907            E61B

Return from CIO with the status in the Y register.

CIRTN2
58909            E61D

Return from CIO with the status in ICSTAZ (35).

COMENT
58941         E63D

Compute the handler entry point using HATABS (794) and COMTAB (59081).

GOHAND
59017         E689

Jump indirectly to the device handler. An indirect jump, in this case, means fooling the 6502 into thinking that the address you want to jump to is actually the one you want to RTS to. This involves playing with the stack and is a pretty neat trick you may want to look at.

DEVSRC
59038         E69E

Find a particular device in the handler address table.

COMTAB
59081         E6C9

This is a table of offsets into the handler entry point table for the desired device. It is used to find the correct vector for the given command.

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