The Programmer's Guide to TRSDOS Version 6 - Tim Mann's Home ...

Exit:
A Error return code
CF Set if a new file was created
Z Set if no error is encountered during the INIT.
7.6.44 @IPL SVC-00
This SVC will reboot the system. It functions the same as pressing the hardware RESET
button. A usable booting system disk must be available in physical drive 0.
Registers Affected: Not applicable
7.6.45 @KBD SVC-08
This SVC will scan the *KI device and return the fetched character, if any character is
available. Note that it is possible to generate an end-of-file (EOF) error from the
physical keyboard (NZ with A=X'1C'). Consult the DOS manual for your particular
installation to ascertain what key entry establishes the EOF indication. On the TRS-80
Model 4, for instance, the entry generates the EOF.
Registers Affected: AF, DE.
Exit:
A Contains the value of the key depressed or error return code.
Z Set to indicate register-A contains the entered key code. If reset, then
either no key was depressed or an error occurred. Register-A will contain a
zero (X'00') under no-key, no-error. Register-A will contain a non-zero
error code if an error was detected during the character "get" (perhaps a
route?).
7.6.46 @KEY SVC-01
This SVC will continuously scan the *KI device until a character is available. It will
not return until a character is available.
Registers Affected: AF, DE.
Exit:
A Contains the character entered or error code.
Z Set if no error is encountered.
7.6.47 @KEYIN SVC-09
This SVC will accept a line of input until terminated by either an or .
During the input, the routine will display the entries. Backspace, tab, and line delete
are supported. KEYIN exits with the cursor in whatever state it was in at the time KEYIN
was entered.
Registers Affected: AF, BC, DE.
Entry:
HL Pointer to user line buffer of length = B+1.
B Maximum number of characters to input.
C Should contain a zero (possible enhancement of KEYIN will use register C to
contain a fill character).
Exit:
B Contains the actual number of characters input.
CF Set if terminated the input.
Z Set if no error was encountered.
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