Intermec PEN*KEY 6100, Руководство программиста

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SECTION 6 Conversions and Interfaces
6-94 PEN*KEY
R
6100 Computer Programmer’s Reference Guide
INT 16h, Function AH = 10h: Read Next Extended ASCII Character
BIOS
If there is no key in the buffer, pend until a key is pressed. This function must
issue INT 15h, Function 90h (Device Busy) with AL set to 2 (Keyboard) to inform
the operating system that no key is available and that another task may be
started. This function does not filter character codes for 83/84Ćstyle keyboard
compatibility. Control is returned only when a key is available and the key is
removed from the keyboard buffer. A command must be sent to the keyboard to
update the LED settings, to ensure that the keyboard LEDs match the current
flag settings.
On Entry:
AH = 10h
On Return:
AX = Character code
"
NOTE: There could be some PL/N compatibility issues, since the scan code returned in the AH reg-
ister in the 4000 BIOS is zero when AL is a valid ASCII character – such as some of the ALT-
character combinations. See the chart showing the character codes returned by INT 16h, in
the Standard Keyboard Interface topic, on page 6-35.
INT 16h, Function AH = 11h: Set Zero Flag if Extended Key Buffer Empty
BIOS
The key is not removed from the buffer. If the keyboard buffer does not contain
a key, the zero flag is set. This function does not filter character codes for the
83/84Ćstyle keyboards. A command must be sent to the keyboard to update the
LED settings, to ensure that the keyboard LEDs match the current flag settings.
This could create some PL/N compatibility issues since the scan code returned in
the AH register in the 4000 BIOS is zero when AL is a valid ASCII character.
On Entry:
AH = 11h
On Return:
Zero = Set flag if the keyboard buffer is empty
AX = Character code
6. Conversions and
Interfaces