Intermec PEN*KEY 6100, Руководство программиста

Страница: 150 / 328

SECTION 6 Conversions and Interfaces
6-14 PEN*KEY
R
6100 Computer Programmer’s Reference Guide
Standard Keyboard Interface: Interrupt 09h
This interface is for both the internal keypad and an external keyboard.
Matrix scan codes are converted to PCĆcompatible scan codes before Interrupt
09h is issued. Standard scan codes are read from port 60h. If the scan code is
not a request for an internal function or a control key press, both the character
code and scan code (two bytes) are placed in a 16Ćword circular buffer at the posiĆ
tion pointed to by the keyboard tail buffer pointer. The tail pointer is then inĆ
cremented by two and allowed to wrap around the buffer.
The entire keyboard interface is described later in this publication in the
StanĆ
dard Keyboard Interface paragraph, on page 6Ć35.
Display Services: Interrupt 10h
A standard VGA BIOS is provided. The software interface to the display hardĆ
ware is through function calls to the BIOS interrupt 10h. The function number
is placed in the AH register. Other registers are loaded with the values required
by the individual function and then the call to the interrupt is made. Each indiĆ
vidual function is described in detail in the following pages.
Equipment Determination: Interrupt 11h
This function returns the equipment information stored in the word located at
40:10h in the BIOS data area. The organization of the word is defined as folĆ
lows:
Bits Description
15-14 Number of printer channels
13
Internal modem installed
12 joystick installed
11-9 Number of RSĆ232 channels
8 (Not used)
7-6 Number of diskette drives (if bit 0 = 1)
0 = One drive
1 = Two drives
5-4 Initial video mode
0 = Not used
1 = 40x25 color
2 = 80x25 color
3 = 80x25 B/W
3 (Not used)
2 Pointing device installed
1 Math coprocessor installed
0 Diskette available for boot
On Entry:
None
On Return:
AX = Equipment information
6. Conversions and
Interfaces