Datasheet EM83049 Datasheet (ELAN)

GENERAL DESCRIPTION

The EM83049 microcontroller is dedicated to a keyboard encoder ,specially designed for IBM PC AT,XT and
all compatible machines. The EM83049 controll all scan codes, three LEDs status, scan timing and communications
between the keyboard and PC. It is easy to implement a high performance, low cost keyboard with the minimal
external components.

FEATURES

• Low cost - eliminate need external components.

• Phantom key detects.

• RC oscillator ( 1.8432MHz ).

• Support scan code set 1 ,2 and 3.

• Support PC AT,XT and PS/2 keyboard .

• Low power CMOS device technology.

• Internal pull-up resistor.

• Tri-state outputs for easy board application.

• 40 Pin DIP package.

• Built-in 4K ROM.

• Support WINDOWS

• 101/102/104 keys or other special application keyboard encoder.

• WINDOWS is registered trademarks of Microsoft corperation.

TM

keys.

EM83049

EM83049

KEYBOARD ENCODER

KEYBOARD ENCODER

APPLICATION

• IBM PC/AT,XT or compatible machine keyboard.

• IBM PS/2 model 30,50,60,80 or compatible machine keyboard.

• Japanese keyboard.

• Korean keyboard.

PIN ASSIGNMENTS

VSS

DATA

CLK

P90
P91

P50
P51
P52
P53
P54
P55
P56
P57
P80
P81

NC

NC
NC
XT
NC

EM83049

1
2
3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20

40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21

OSCO
OSCR
VDD
CAPS
NUM
SCROLL
P67
P66
P65
P64
P63
P62
P61
P60
P87
P86
P85
P84
P83
P82

* This specification are subject to be changed without notice.

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KEYBOARD ENCODER

PIN DESCRIPTIONS

Symbol I/O Function

P50 O Column 0 Low output scan line, 3-state
P51 O Column 1 Low output scan line, 3-state

P52 O Column 2 Low output scan line, 3-state
P53 O Column 3 Low output scan line, 3-state
P54 O Column 4 Low output scan line, 3-state
P55 O Column 5 Low output scan line, 3-state
P56 O Column 6 Low output scan line, 3-state
P57 O Column 7 Low output scan line, 3-state
P80 O Column 8 Low output scan line, 3-state
P81 O Column 9 Low output scan line, 3-state
P82 O Column 10 Low output scan line, 3-state
P83 O Column 11 Low output scan line, 3-state
P84 O Column 12 Low output scan line, 3-state
P85 O Column 13 Low output scan line, 3-state
P86 O Column 14 Low output scan line, 3-state
P87 O Column 15 Low output scan line, 3-state
P90 O Column 16 Low output scan line, 3-state
P91 O Column 17 Low output scan line, 3-state
VSS I Ground
SCROLL O Scroll Lock Indicator
NUM O NUM Lock Indicator
CAPS O Caps Lock Indicator
P60 I Row 0 Input scan line, internal pull high ( 10KΩ )
P61 I Row 1 Input scan line, internal pull high ( 10KΩ )
P62 I Row 2 Input scan line, internal pull high ( 10KΩ )
P63 I Row 3 Input scan line, internal pull high ( 10KΩ )
P64 I Row 4 Input scan line, internal pull high ( 10KΩ )
P65 I Row 5 Input scan line, internal pull high ( 10KΩ )
P66 I Row 6 Input scan line, internal pull high ( 10KΩ )
P67 I Row 7 Input scan line, internal pull high ( 10KΩ )
CLK I/O CLOCK line for IBM communication , internal pull high ( 2.2KΩ )
DATA I/O DATA line for IBM communication , internal pull high ( 2.2KΩ )
V

DD

OSCO O CLOCK output
OSCR I Connect 51K OHM resistor for 1.8432 MHz oscillation
XT I "1" or Floating=AT, "0"=XT, internal pull high.

I +5V Power Supply

EM83049

* This specification are subject to be changed without notice.

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KEYBOARD ENCODER

FUNCTION DESCRIPTIONS

Keyboard buffer

The keyboard will buffer 16 bytes in a first-in-first-out order when the system is able to receive scan codes
from the keyboard. The response codes and repeated codes will not be buffered. If keystrokes generate a
multiple-byte sequence, the entire sequence must fit into the buffer or the keystroke is discarded and a buffer­overrun condition occurs.

Power-on Reset and self test

The duration of the keyboard Power-on-Reset(POR) should be within 150 milliseconds and 2 seconds after
the power is applied to the keyboard.
After executing POR , the keyboard executes a self test. The LEDs are turned on at the beginning and off at
the end of the self test. The self test takes a minimum 300 milliseconds and a maximum 500 milliseconds.
If the self test is successful, a completion code AA hex is sent to the system and the keyboard starts scanning.
If the self test fails, and error code is sent, the keyboard is disabled and waits for a command from the system.
The completion codes are sent between 450 milliseconds and 2.5 seconds after POR, and between 300 and
500 milliseconds after a RESET command is acknowledged.

EM83049

Keyboard data output

When the keyboard is ready to send data to the system, it first checks clock and data lines. If either one is in
the low state, data is stored in the keyboard buffer. If both are in the high state, keyboard starts clocking data
out. Data will be valid before the trailing edge and after the leading edge of the clock pulse. During the
transmission the keyboard checks the clock line at least every 60 microseconds . If the system lowers the clock
lines before the leading edge of the 10th clock, the keyboard should stop sending, then buffer the data and
return clock and data lines to high state.

Keyboard data input

When the system is ready to send data to the keyboard, it first checks clock line to see if keyboard is sending
data. If keyboard is not sending data or it is sending data but has not reached the 10th clock, the system can
inhibit the interface by forcing the clock line low for more than 60 microseconds and prepares to send data.
The keyboard checks clock line status at least every 5 milliseconds. If a system Request to Send(RTS) is
detected, the keyboard clocks 11 bits in. After the 10th bit, the keyboard checks for a high state in data line
then pulls it low and clocks one more bit to signal the system that data has been received. If data is low after
the 10th bit, it indicates a frame error. The keyboard should continue to count until data line goes high, then
pulls it low and issues a RESEND to the system.

Command from the system

The system can send commands to the keyboard at any time. The keyboard needs to respond within 20
milliseconds, unless the system prevents keyboard output, when doing self test or executing a RESET.
The following are the keyboard input commands and the actions that keyboard needs to take.

Set /Reset Status indicators ( Hex ED )

- Responds ACK.

- Receives option byte.

* This specification are subject to be changed without notice.

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- Responds ACK.

- Updates status indicators.

- Returns to previous scanning state.

Echo ( Hex EEH )

- Responds with EE hex.

- Returns to previous scanning state.

Invalid commands ( Hex EF and F1 )

- Returns a RESEND command.

- Returns to previous scanning state.

Select Alternate Scan Codes ( Hex F0 )

- Responds ACK.

- Clears output buffer.

- Sets the default typematic rate/delay.

- Clears last typematic key.

- Receives option byte.

- Responds ACK.

- Option byte =
01 : selects scan code set 1
02 : selects scan code set 2
03 : selects scan code set 3

- Returns to previous scanning rate.

EM83049

KEYBOARD ENCODER

Read ID (F2)

- Responds with ACK.

- Discontinues scanning.

- Sends two ID bytes. The second byte will be sent within 500 uS after first byte.

- Resumes scanning.

Set Typematic Rate/Delay ( Hex F3 )

- Responds ACK.

- Receives rate/delay value byte

- Responds ACK.

- Set rate/delay (* Note 1)

- Returns to previous scanning state.

* Note 1

1. Repeat period = ( 8+A ) x ( 2B) x 0.00417 seconds

A : binary value of bits 2, 1, and 0.
B : binary value of bits 4 and 3.

2. Delay = ( C +1 ) x 250 milliseconds

C : binary value of bits 6 and 5. Bit 7 is always 0.

* This specification are subject to be changed without notice.

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KEYBOARD ENCODER

bit 4~ bit 0 typematic rate ± 20% bit 4~ bit 0 typematic rate ± 20%

00000 30.0 10000 7.5
00001 26.7 10001 6.7

00010 24.0 10010 6.0
00011 21.8 10011 5.5
00100 20.0 10100 5.0
00101 18.5 10101 4.6
00110 17.1 10110 4.3
00111 16.0 10111 4.0
01000 15.0 11000 3.7
01001 13.3 11001 3.3
01010 12.0 11010 3.0
01011 10.9 11011 2.7
01100 10.0 11100 2.5
01101 9.2 11101 2.3
01110 8.6 11110 2.1
01111 8.0 11111 2.0

EM83049

3. Default rate = 10.9 chars/sec + 20%

Default delay = 500 mS ± 20%

Enable ( Hex F4 )

- Responds with ACK.

- Clears output buffer.

- Clears last typematic key.

- Start scanning.

Default Disable (Hex F5)

- Responds with ACK.

- Resets all conditions to power-on state.

- Clears output buffer.

- Sets the default key type ( scan code set 3 only ).

- Set the default typematic rate/delay.

- Clears last typematic key.

- Stops scanning,

Set Default (Hex F6 )

- Responds with ACK.

- Resets all conditions to power-on state.

- Clears output buffer.

- Sets the default key type ( scan code set 3 only ).

- Set the default typematic rate/delay.

- Clears last typematic key.

- Continues scanning,

Set All Keys ( Hex F7,F8,F9,FA )

* This specification are subject to be changed without notice.

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- Responds ACK.

- Clears output buffer.

- Sets all key type (affect only scan code set 3 operation).
F7 : Typematic
F8 : Make/Break
F9 : Make
FA : Typematic/Make/Break

- Returns to previous scanning rate.

Set Key Type ( Hex FB,FC,FD )

- Responds ACK.

- Clears output buffer.

- Receives key ID byte

- Responds ACK.

- Sets key ID type (affect only scan code set 3 operation).
FB : Typematic
FC : Make/Break
FD : Make

- Returns to previous scanning rate.

EM83049

KEYBOARD ENCODER

Resend ( Hex FE )

- Sends the previous output again. If the previous byte is RESEND, the last byte before RESEND shall be sent.

Reset ( Hex FF )

- Responds ACK.

- Checks clock and data lines - Reset in the high state for at least 500 microseconds or receives another command.

- Default to scan code set 2.

Command to the system

The following are the keyboard output commands.

Acknowledge ( Hex FA )

The keyboard sends an acknowledge in response to any valid command from the system except for RESEND
and ECHO.

BAT Completion Code ( Hex AA )

This command is issued after successful completion of keyboard self test.

Echo ( Hex EE )

The keyboard sends this code in response to an ECHO command.

* This specification are subject to be changed without notice.

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EM83049

KEYBOARD ENCODER

Keyboards ID ( Hex 83AB )

The 2 byte ID is issued to respond to READ ID command. The low byte is sent first, followed by the high byte.

Keyboard buffer Overrun ( Hex 00 or FF )

If keyboard buffer overflows, the overrun code will replace the last byte in the buffer. If the keyboard is using
scan code set 1 , the code is hex FF. For sets 2 and 3, the code is hex 00.

Resend ( Hex FE )

When the keyboard receives an invalid input or any input with incorrect parity, the RESEND command is sent.

Keyboard Scan Code Table

The keyboard contains 3 scan code sets. The system defaults to scan code set 2, but can be switched to set 1 or
set 3 . The following tables show the key numbers and three scan code sets in hexadecimal values. All the keys
are typematics except for the pause key. When a key is pressed down, the make scan code is sent to the
system. When the key is released, its break code is sent. If two or more keys are held down, only the last key
pressed repeats at the typematic rate. Typematic operation stops when the last pressed key is released, even if
other keys are being released or some other keys are still held down.

The following table shows three scan code sets used in the keyboard.

scan code set 1

Key Number Make code Break code Key Number Make code Break code

1 29 A9 47 2D AD
20282 482EAE
30383 492FAF
4 04 84 50 30 B0
5 05 85 51 31 B1
6 06 86 52 32 B2
7 07 87 53 33 B3
8 08 88 54 34 B4

9 09 89 55 35 B5
10 0A 8A 57 36 B6
11 0B 8B 58 1D 9D
12 0C 8C 60 38 B8
13 0D 8D 61 39 B9
15 0E 8E 62 E0 38 E0 B8
16 0F 8F 64 E0 1D E0 9D
17 10 90 90 45 C5
18 11 91 91 47 C7
19 12 92 92 4B CB
20 13 93 93 4F CF
21 14 94 96 48 C8
22 15 95 97 4C CC

* This specification are subject to be changed without notice.

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KEYBOARD ENCODER

Key Number Make code Break code Key Number Make code Break code

23 16 96 98 50 D0
24 17 97 99 52 D2
25 18 98 100 37 B7
26 19 99 101 49 C9
27 1A 9A 102 4D CD
28 1B 9B 103 51 D1

29 @1 2B AB 104 53 D3

30 3A BA 105 4A CA
31 1E 9E 106 4E CE
32 1F 9F 108 E0 1C E0 9C
33 20 A0 110 01 81
34 21 A1 112 3B BB
35 22 A2 113 3C BC
36 23 A3 114 3D BD
37 24 A4 115 3E BE
38 25 A5 116 3F BF
39 26 A6 117 40 C0
40 27 A7 118 41 C1
41 28 A8 119 42 C2

42 @2 2B AB 120 43 C3

43 1C 9C 121 44 C4
44 2A AA 122 57 D7

45 @2 56 D6 123 58 D8

46 2C AC 125 46 C6

Key No. Base Case,or Shift + Nun Lock Shift Case @3 Num Lock

Make/Break Make/Break Make/Break

75 E0 52 / E0 D2 E0 AA E0 52 E0 2A E0 52

/ E0 D2 E0 2A / E0 D2 E0 AA

76 E0 53 / E0 D3 E0 AA E0 53 E0 2A E0 53

/ E0 D3 E0 2A / E0 D3 E0 AA

79 E0 4B / E0 CB E0 AA E0 4B E0 2A E0 4B

/ E0 CB E0 2A / E0 CB E0 AA

80 E0 47 / E0 C7 E0 AA E0 47 E0 2A E0 47

/ E0 C7 E0 2A / E0 C7 E0 AA

81 E0 4F / E0 CF E0 AA E0 4F E0 2A E0 4F

/ E0 CF E0 2A / E0 CF E0 AA

83 E0 48 / E0 C8 E0 AA E0 48 E0 2A E0 48

/ E0 C8 E0 2A / E0 C8 E0 AA

84 E0 50 / E0 D0 E0 AA E0 50 E0 2A E0 50

/ E0 D0 E0 2A / E0 D0 E0 AA

85 E0 49 / E0 C9 E0 AA E0 49 E0 2A E0 49

/ E0 C9 E0 2A / E0 C9 E0 AA

86 E0 51 / E0 D1 E0 AA E0 51 E0 2A E0 51

/ E0 D1 E0 2A / E0 D1 E0 AA

89 E0 4D / ED CD E0 AA E0 4D E0 2A E0 4D

/ E0 CD E0 2A / E0 CD E0 AA

* This specification are subject to be changed without notice.

5.2.1997

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Note .

EM83049

KEYBOARD ENCODER

Key No. Scan Code Make/Break Shift Case Make/Break @3

95 E0 35 / E0 B5 E0 AA E0 35 / E0 B5 E0 2A

Key No. Scan Code Ctrl Case, Shift Case Alt Case

Make/Break Make/ Break Make/Break

124 E0 2A E0 37 E0 37 / E0 B7 54 / D4

/ E0 B7 E0 AA

Key No. Make Code Ctrl Key Pressed
126 @4 E1 1D 45 E1 9D C5 E0 46 E0 C6

@1 : 101-key keyboard only.
@2 : 102-key keyboard only.
@3 : If the left Shift key is held down, the AA/2A shift make and break is sent with the other scan codes.

If the right Shift key is held down, B6/36 is sent. If both Shift keys are down, both sets of codes are
sent with the other scan code.

@4 : This key is not typematic. All associated scan codes occur on the make of the key.

scan code set 2

Key Number Make code Break code Key Number Make code Break code

1 0E F0 0E 47 22 F0 22
2 16 F0 16 48 21 F0 21
3 1E F0 1E 49 2A F0 2A
4 26 F0 26 50 32 F0 32
5 25 F0 25 51 31 F0 31
6 2E F0 2E 52 3A F0 3A
7 36 F0 36 53 41 F0 41
8 3D F0 3D 54 49 F0 49

9 3E F0 3E 55 4A F0 4A
10 46 F0 46 57 59 F0 59
11 45 F0 45 58 14 F0 14
12 4E F0 4E 60 11 F0 11
13 55 F0 55 61 29 F0 29
15 66 F0 66 62 E0 11 E0 F0 11
16 0D F0 0D 64 E0 14 E0 F0 14
17 15 F0 15 90 77 F0 77
18 1D F0 1D 91 6C F0 6C
19 24 F0 24 92 6B F0 6B
20 2D F0 2D 93 69 F0 69
21 2C F0 2C 96 75 F0 75
22 35 F0 35 97 73 F0 73
23 3C F0 3C 98 72 F0 72
24 43 F0 43 99 70 F0 70
25 44 F0 44 100 7C F0 7C
26 4D F0 4D 101 7D F0 7D
27 54 F0 54 102 74 F0 74
28 5B F0 5B 103 7A F0 7A

29 @5 5D F0 5D 104 71 F0 71

* This specification are subject to be changed without notice.

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KEYBOARD ENCODER

Key Number Make code Break code Key Number Make code Break code

30 58 F0 58 105 7B F0 7B
31 1C F0 1C 106 79 F0 79
32 1B F0 1B 108 E0 5A E0 F0 5A
33 23 F0 23 110 76 F0 76
34 2B F0 2B 112 05 F0 05
35 34 F0 34 113 06 F0 06
36 33 F0 33 114 04 F0 04
37 3B F0 3B 115 0C F0 0C
38 42 F0 42 116 03 F0 03
39 4B F0 4B 117 0B F0 0B
40 4C F0 4C 118 83 F0 83
41 52 F0 52 119 0A F0 0A

42 @6 5D F0 5D 120 01 F0 01

43 5A F0 5A 121 09 F0 09
44 12 F0 12 122 78 F0 78

45 @6 61 F0 61 123 07 F0 07

46 1A F0 1A 125 7E F0 7E

Key No. Base Case,or Shift Case @7 Num Lock

Shift + Nun Lock Make/Break Make/Break

Make/Break

75 E0 70 / E0 F0 70 E0 F0 12 E0 70 E0 12 E0 70

/ E0 F0 70 E0 12 / E0 F0 70 E0 F0 12

76 E0 71 / E0 F0 71 E0 F0 12 E0 71 E0 12 E0 71

/ E0 F0 71 E0 12 / E0 F0 71 E0 F0 12

79 E0 6B / E0 F0 6B E0 F0 12 E0 6B E0 12 E0 6B

/ E0 F0 6B E0 12 / E0 F0 6B E0 F0 12

80 E0 6C / E0 F0 6C E0 F0 12 E0 6C E0 12 E0 6C

/ E0 F0 6C E0 12 / E0 F0 6C E0 F0 12

81 E0 69 / E0 F0 69 E0 F0 12 E0 69 E0 12 E0 69

/ E0 F0 69 E0 12 / E0 F0 69 E0 F0 12

83 E0 75 / E0 F0 75 E0 F0 12 E0 75 E0 12 E0 75

/ E0 F0 75 E0 12 / E0 F0 75 E0 F0 12

84 E0 72 / E0 F0 72 E0 F0 12 E0 72 E0 12 E0 72

/ E0 F0 72 E0 12 / E0 F0 72 E0 F0 12

85 E0 7D / E0 F0 7D E0 F0 12 E0 7D E0 12 E0 7D

/ E0 F0 7D E0 12 / E0 F0 7D E0 F0 12

86 E0 7A / E0 F0 7A E0 F0 12 E0 7A E0 12 E0 7A

/ E0 F0 7A E0 12 / E0 F0 7A E0 F0 12

89 E0 74 / E0 F0 74 E0 F0 12 E0 74 E0 12 E0 74

/ E0 F0 74 E0 12 / E0 F0 74 E0 F0 12

Key No. Scan Code Make/Break Shift Case Make/Break @7

95 E0 4A / E0 F0 4A E0 F0 12 E0 4A / E0 F0 4A E0 12

Key No. Scan Code Ctrl Case, Shift Case Alt Case

Make/Break Make/ Break Make/Break

124 E0 12 E0 7C E0 7C / E0 F0 7C 84 / F0 84

/ E0 F0 7C E0 F0 12

* This specification are subject to be changed without notice.

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Key No. Make Code Ctrl Key Pressed

126 @8 E1 14 77 E1 F0 14 F0 77 E0 7E E0 F0 7E

Note .

@5 : 101-key keyboard only.
@6 : 102-key keyboard only.
@7 : If the left Shift key is held down, the F0 12/12 shift make and break is sent with the other scan codes.

If the right Shift key is held down, F0 59/59 is sent. If both Shift keys are down, both sets of codes

are sent with the other scan code.

@8 : This key is not typematic. All associated scan codes occur on the make of the key.

scan code set 3

Key number Make Code Break Code Default Key State

EM83049

KEYBOARD ENCODER

1 0E F0 0E Typematic
2 16 F0 16 Typematic
3 1E F0 1E Typematic
4 26 F0 26 Typematic
5 25 F0 25 Typematic
6 2E F0 2E Typematic
7 36 F0 36 Typematic
8 3D F0 3D Typematic

9 3E F0 3E Typematic
10 46 F0 46 Typematic
11 45 F0 45 Typematic
12 4E F0 4E Typematic
13 55 F0 55 Typematic
15 66 F0 66 Typematic
16 0D F0 0D Typematic
17 15 F0 15 Typematic
18 1D F0 1D Typematic
19 24 F0 24 Typematic
20 2D F0 2D Typematic
21 2C F0 2C Typematic
22 35 F0 35 Typematic
23 3C F0 3C Typematic
24 43 F0 43 Typematic
25 44 F0 44 Typematic
26 4D F0 4D Typematic
27 54 F0 54 Typematic
28 5B F0 5B Typematic

29 @9 5C F0 5C Typematic

30 14 F0 14 Make/Break
31 1C F0 1C Typematic
32 1B F0 1B Typematic
33 23 F0 23 Typematic
34 2B F0 2B Typematic
35 34 F0 34 Typematic
36 33 F0 33 Typematic

* This specification are subject to be changed without notice.

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KEYBOARD ENCODER

Key number Make Code Break Code Default Key State

37 3B F0 3B Typematic
38 42 F0 42 Typematic
39 4B F0 4B Typematic
40 4C F0 4C Typematic
41 52 F0 52 Typematic

42 @10 53 F0 53 Typematic

43 5A F0 5A Typematic
44 12 F0 12 Make/Break

45 @10 13 F0 13 Typematic

46 1A F0 1A Typematic
47 22 F0 22 Typematic
48 21 F0 21 Typematic
49 2A F0 2A Typematic
50 32 F0 32 Typematic
51 31 F0 31 Typematic
52 3A F0 3A Typematic
53 41 F0 41 Typematic
54 49 F0 49 Typematic
55 4A F0 4A Typematic
57 59 F0 59 Make/Break
58 11 F0 11 Make/Break
60 19 F0 19 Make/Break
61 29 F0 29 Typematic
62 39 F0 39 Make only
64 58 F0 58 Make only
75 67 F0 67 Make only
76 64 F0 64 Typematic
79 61 F0 61 Typematic
80 6E F0 6E Make only
81 65 F0 65 Make only
83 63 F0 63 Typematic
84 60 F0 60 Typematic
85 6F F0 6F Make only
86 6D F0 6D Make only
89 6A F0 6A Typematic
90 76 F0 76 Make only
91 6C F0 6C Make only
92 6B F0 6B Make only
93 69 F0 69 Make only
95 77 F0 77 Make only
96 75 F0 75 Make only
97 73 F0 73 Make only
98 72 F0 72 Make only
99 70 F0 70 Make only

100 7E F0 7E Make only
101 7D F0 7D Make only
102 74 F0 74 Make only
103 7A F0 7A Make only

* This specification are subject to be changed without notice.

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KEYBOARD ENCODER

Key number Make Code Break Code Default Key State

104 71 F0 71 Make only
105 84 F0 84 Make only
106 7C F0 7C Typematic
108 79 F0 79 Make only
110 08 F0 08 Make only
112 07 F0 07 Make only
113 0F F0 0F Make only
114 17 F0 17 Make only
115 1F F0 1F Make only
116 27 F0 27 Make only
117 2F F0 2F Make only
118 37 F0 37 Make only
119 3F F0 3F Make only
120 47 F0 47 Make only
121 4F F0 4F Make only
122 56 F0 56 Make only
123 5E F0 5E Make only
124 57 F0 57 Make only
125 5F F0 5F Make only
126 62 F0 62 Make only

Note .

@9 : 101-key keyboard only
@10 : 102-key keyboard only

New key codes for scan set 1:

New key Make Break

LWIN E0 5B E0 DB

RWIN E0 5C E0 DC

APP E0 5D E0 DD

N-CHG (131) 7B FB

CHG (132) 79 F9

ROMA (133) 70 F0

014 7D FD

056 73 F3

107 7E FE

KL F1 X

KR F0 X

* This specification are subject to be changed without notice.

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New key codes for scan set 2:

New key Make Break

LWIN E0 1F E0 F0 1F

RWIN E0 27 E0 F0 27

APP E0 2F E0 F0 2F

N-CHG (131) 67 F0 67

CHG (132) 64 F0 64

ROMA (133) 13 F0 13

014 6A F0 6A

056 51 F0 51

107 6D F0 6D

KL F1 X

KR F2 X

New key codes for scan set 3:

EM83049

KEYBOARD ENCODER

New key Make Break

LWIN 8B F0 8B

RWIN 8C F0 8C

APP 8D F0 8D

N-CHG (131) 85 F0 85

CHG (132) 86 F0 86

ROMA (133) 87 F0 87

014 5D F0 5D

056 51 F0 51

107 7B F0 7B

KL F1 X

KR F2 X

* This specification are subject to be changed without notice.

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126

120

112110

113

115114

119

118117116

123122121

125124

1

23 45

17

16

30

44

58

1

16

30

44

58

18 19 20

32 33

31

46 47

60

112110

113

2345

17

18 19 20

32 33

31

46 47

60

112110

113

21 22

34

35

48 49 50

115114

21 22

34

35

48 49 50

115114

876

9

23

24

36

37

51

52

61

11

10

26

25

39

38

53

27

41

40

55

54

62

29

28

43

57

64

15

13

12

Fig 1. The 101-key keyboard layout

120

119

118117116

12

876

9

23

24

36

37

51

52

61

11

10

26

25

39

38

53

27

41

40

55

54

62

123122121

15

13

28

43

42

57

64

Fig 2. The 102-key keyboard layout

120

119

118117116

123122121

75

76

75

76

85

86

89

126

89

126

90

91

92

93

85

90

86

91

92

93

80

81

83

8479

125124

80

81

83

8479

125124

100

101

102

103

104

103

100

101

102

104

105

106

108

105

106

108

95

96

97

98

99

95

96

97

98

99

2345

1

17

16

30

44

58

18 19 20

31

46 47

LWIN

32 33

60

21 22

34

35

48 49 50

876

9

23

24

36

37

38

51

52

61

Fig 3. The 104-key keyboard layout

* This specification are subject to be changed without notice.

13

RWIN

15

28

42

APP

57

64

75

76

43

85

80

81

83

89

8479

90

86

91

92

93

99

100

95

101

96

102

97

103

98

104

5.2.1997

105

106

108

15

12

11

10

26

25

39

53

27

41

40

55

54

62

ABSOLUTE MAXIMUM RATINGS

Parameter Sym. Ratings

EM83049

KEYBOARD ENCODER

Supply Voltage V
Input Voltage V

Output Voltage V
Temperature under bias T

Storage temperature T

CC

IN

OUT

B

S

-0.5V to +7V

-0.3V to +6V

-0.3V to +6V

0°C to 70°C

-65°C to 150°C

DC ELECTRICAL CHARACTERISTICS

Parameter Sym. Min. Typ. Max. Unit Condition

Operating voltage V
Operating supply current I

Input leakage I
Input high voltage V

Input low voltage V
Output high voltage V
Output low voltage V
Output low voltage for LEDS V
Internal Pull-high resistance ( port 6,9 ) R
Internal Pull-high resistance for R
DATA, CLK

CCI

IL

PH1

PH2

4.5 5 5.5 V

CC

3 mA Fosc=1.8432MHz

±1 µAVIN=VCC ,V

2.0 V

IH

IL

2.4 V I

OH1

OL1

OL3

0.8 V

0.4 V IOL = 3.0 mA

3.2 V IOL = 10 mA

4.7 10 KΩ

1.5 2.2 3 KΩ

= - 6.0 mA

OH

SS

AC ELECTRICAL CHARACTERISTICS

Parameter Sym. Min. Typ. Max. Unit

Time from DATA transition to falling edge of CLK T1 5 25 µS
Time from rising edge of CLK to DATA transition T2 5 T4 - 5 µS
Duration of CLK inactive T3 30 40 50 µS
Duration of CLK active T4 30 40 50 µS

Time to auxiliary device inhibit after clock 11 to ensure T5 50 µS
the auxiliary device does not start another transmission
Time from inactive to active CLK transition, used to time T6 5 25 µS
when auxiliary device samples DATA
System clock FCLK 1.843 MHz

* This specification are subject to be changed without notice.

5.2.1997

16

TIMING DIAGRAMS

EM83049

KEYBOARD ENCODER

CLK

T1

DATA

I/O

Inhibit

CLK

Start Bit

DATA

APPLICATION CIRCUIT

1ST
CLK

Start Bit

2nd
CLK

T3

T4

T2

Bit 0

Fig 3. Keyboard output data timings

1ST
CLK

T3

Bit 0

2nd
CLK

T4

T6

Fig 4. Keyboard input data timings

10th
CLK

Parity Bit

9th
CLK

11th
CLK

T5

Parity Bit

Stop Bit

10th
CLK

11th
CLK

Stop Bit

XT

DATA

CLK

C16
C17

VCC

10µ

SCROLL

NUM

OSCO

R-OSCI

VDD

CAPS

NUM

SCROLL

P67
P66
P65
P64
P63
P62
P61
P60
P87
P86
P85
P84
P83
P82

51K

40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21

CAPS

R7
R6
R5
R4
R3
R2
R1

R0
C15
C14
C13
C12
C11
C10

U1

1

VSS

2

NC

3

DATA

4

CLK

5

P90

6

P91

7

NC

8

NC

9

XT

10
11
12
13
14
15
16
17
18
19
20

NC
P50
P51
P52
P53
P54
P55
P56
P57
P80
P81

EM83049

C0
C1
C2
C3
C4
C5
C6
C7
C8
C9

C10

C11

C12

C13

C14

C15

C16

C17

R0

C0

126

C1

017

C2

018

C3

019

C4

020

C5

023

C6

024

C7

025

C8

026

C9

125

014

091

096

101

106

KL

R1

016

030

114

021

022

028

118

027

015

092

097

102

107

044

LWIN

R2

031

032

033

034

037

038

039

040

029

093

098

103

108

057

RWIN

110

045

115

035

036

117

041

060

122

061

099

104

083

R3

R4

R5

R6

R7

064

046

047

048

049

052

053

054

042

043

090

095

100

131

132

133

050

051

056

APP

055

062

123

084

089

105

079

058

001

112

113

006

007

013

119

012

120

076

075

085

080

116

002

003

004

005

008

009

010

011

124

121

086

081

KR

* This specification are subject to be changed without notice.

5.2.1997

17