Keyboard

4.2.3Keyboard Matrix

The PRoC LP RDK keyboard matrix has 18 columns and 8 rows. Key presses generate a GPIO interrupt when a column is connected (shorted) to a row. The keyboard then scans the matrix to determine which keys have been pressed.

The RDK keyboard matrix with the USB scan codes are shown in Table 4-1.

Table 4-1. RDK Keyboard Matrix

 

Row

Row

Row

Row

Row

Row

Row

Row

 

0

1

2

3

4

5

6

7

Column 0

0x09

0x0A

0x19

0x05

0x17

0x15

0x21

0x22

Column 1

0x0D

0x0B

0x10

0x11

0x1C

0x18

0x24

0x23

Column 2

0x0E

0x3F

0x36

NA

0x30

0x0C

0x25

0x2E

Column 3

0x0F

NA

0x37

NA

0x40

0x12

0x26

0x41

Column 4

0x33

0x34

NA

0x38

0x2F

0x13

0x27

0x2D

Column 5

0x31

0x3E

0x28

0x2C

0x2A

NA

0x43

0x42

Column 6

0x5A

0x62

0x54

0x4F

0x5D

0x60

0x45

0x49

Column 7

0x59

NA

0x53

0x51

0x5C

0x5F

0x44

0x4C

Column 8

0x5B

0x63

0x55

0x56

0x5E

0x61

0x4E

0x4B

Column 9

0x07

0x3D

0x06

NA

0x3C

0x08

0x20

0x3B

Column 10

0x16

NA

0x1B

NA

0x39

0x1A

0x1F

0x3A

Column 11

0x04

0x29

0x1D

NA

0x2B

0x14

0x1E

0x35

Column 12

0x58

0x52

0x48

0x50

NA

0x57

0x4D

0x4A

Column 13

NA

0x04

NA

0x40

0x0192

0x47

0x46

0x0223

Column 14

0x02

0x00CD

0x20

NA

0x02

NA

0x0221

0x018A

Column 15

NA

NA

0x10

NA

0x00E9

NA

NA

0x01

Column 16

0x7D

0x00E2

0x80

0x7C

0x00B7

0x00EA

0x022A

NA

Column 17

0x08

0x0225

NA

0x7B

0x0224

0x65

0x00B6

0x00B5

Notes:

 

 

 

 

 

 

 

 

Yellow indicates Multimedia Key (16-bit value)

Red indicates Power Key

Blue indicates Modifier Key

No color indicates a Standard 101 Key

4.2.4Hardware Considerations

The keyboard design uses the BAT400D-7-F schottky diode (D1) and CDH53100LC inductor (L3) for its boost circuitry. These low cost components are used to reduce the over all system cost at the expense of lower boost efficiency and performance. Preliminary characterization data shows a range of 68–81% efficiency for the 1.8–2.7V VBAT voltage range at different temperatures (–10C to 80C). Higher efficiency components such as the ones in the mouse design may be used at the expense of component costs and board size (these low cost components are smaller in size compared to the ones used in the mouse design).

CY4672 Reference Design Guide, Document # 001-16968 Revision **

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Cypress CY4672 manual Keyboard Matrix, Row