DL7942 Datasheet PDF - QiXin
Part Number | DL7942 | |
Description | single chip keyboard encoder | |
Manufacturers | QiXin | |
Logo | ||
There is a preview and DL7942 download ( pdf file ) link at the bottom of this page. Total 22 Pages |
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键盘 IC
GENERAL DESCRIPTION
The DL7942 a single chip keyboard encoder developed for IBM PC AT, IBM PS2 and compatible machine keyboard.
The device detects the key press and release activity, sends the scan code to system, and accepts the command from system.
A high performance, low cost keyboard can be achieved by using the DL7942 with the minimal external components.
FEATURES
Support scan code set 1, 2 and 3.
Support PC AT and PS/2 keyboard.
104/107 keys with with multi media or other special application keyboard encoder.
Support WINDOWS95, 98, 2000 keys.
IBM PC AT or compatible machine keyboard
IBM PS/2 model 30, 50, 60, 80 or compatible machine keyboard.
Phantom key detects.
Built-in RC oscillator with external resistor.
Internal pull-up resistor for inputs.
Tri-state outputs.
Low power CMOS device technology.
APPLICATION
PIN DESCRIPTION
PIN NO
Pin Name
1 GND
2 OSCO
3 DATA
4 CLK
24,5,6,11~15,22,23,21,19,
19,18,17,16,20,25,26
C0~C17
27~34
R0~R7
7,8,9,10
NC
35 SCRL
36 NUM
37 CAPS
38 NC
39 VDD
40 OSCI
Direction
POWER
O
I/O
I/O
Function description
Negative power supply pin
Clock output
Data line of serial port
Clock line of serial port,
O Keyboard matrix scanning output pins
I
-
O
O
O
TEST
POWER
I
Keyboard matrix scanning input pins
No connection
Scroll Lock indicator
Num Lock indicator
CAPS lock indicator
--
Positive power supply pin
External oscillator resistor connection pin
FUNCTION DESCRIPTIONS
The DL7942‘s main function is to detect key press and release activity and to transmit the corresponding scan code, as
well as make and break codes to the system. The device also accepts commands from the system. The communication
between the keyboard and the system is realized via a serial port consists of CLOCK and DATA pins.
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DL7942
Invalid commands-EF, F1(hex)
Returns a RESEND command.
Returns to previous scanning state
键盘 IC
.Echo-EE (hex)
Sends an EE (hex) to the system.
Return to previous scanning state.
Set status indicators-ED (hex)
Sends an ACK to the system.
Receives option byte.
Sends an ACK to the system.
Updates status Indicators.
Returns to previous scanning state.
Command to the system
Acknowledge- FA(hex)
If the keyboard receives an valid command from the system, an ACK Will be send back to the system, except that
the command received is RESEND or ECHO.
BAT Completion Code-AA (hex)
This command is sent to system after successful completion of keyboard BAT.
Buffer overrun 00, FF (hex)
If keyboard buffer overflows, The last byte in the buffer will be replace by 00 or FF.
Scan code set 1-FF,
Scan code sets 2 and 3-00.
Resend –FE(hex)
This command is send to the system after the keyboard receives an invalid code or any incorrect parity.
Echo-EE (hex)
This command is send to the system after the keyboard receives an invalid code or any incorrect parity.
Echo-EE(hex)
This command is send to the system after the keyboard receives an ECHO command.
Keyboards ID –83AB (hex)
The 2-byte ID is send to the system after receives READ ID command. The low byte is sent fist, then high byte is sent.
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Part DetailsOn this page, you can learn information such as the schematic, equivalent, pinout, replacement, circuit, and manual for DL7942 electronic component. |
Information | Total 22 Pages | |
Link URL | [ Copy URL to Clipboard ] | |
Download | [ DL7942.PDF Datasheet ] |
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