![](http://datasheet.mmic.net.cn/90000/5962-9169201QXC_datasheet_3474848/5962-9169201QXC_24.png)
MAX6954
4-Wire Interfaced, 2.7V to 5.5V LED Display
Driver with I/O Expander and Key Scan
24
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REGISTER DATA
REGISTER
POWER-UP
CONDITION
ADDRESS
CODE
(HEX)
D7
D6
D5
D4
D3
D2
D1
D0
Decode Mode
Decode mode enabled
0x01
1
111
1
Global Intensity
1/16 (min on)
0x02
X
XXX0
0
Scan Limit
Display 8 digits: 0, 1, 2, 3, 4, 5, 6, 7
0x03
X
XXX
X
1
Control Register
Shutdown enabled, blink speed is
slow, blink disabled
0x04
0
X
000
0
GPIO Data
Outputs are low
0x05
X
0
000
0
Port Configuration
No key scanning, P0 to P4 are all
inputs
0x06
0
001
111
1
Display Test
Normal operation
0x07
X
XXX
XXX0
Key_A Mask
None of the keys cause interrupt
0x08
0
000
0
Key_B Mask
None of the keys cause interrupt
0x09
0
000
0
Key_C Mask
None of the keys cause interrupt
0x0A
0
000
0
Key_D Mask
None of the keys cause interrupt
0x0B
0
000
0
Digit Type
All are 16 segment or 7 segment
0x0C
0
000
0
Intensity10
1/16 (min on)
0x10
0
000
0
Intensity32
1/16 (min on)
0x11
0
000
0
Intensity54
0x12
0
000
0
Intensity76
1/16 (min on)
0x13
0
000
0
Intensity10a
1/16 (min on)
0x14
0
000
0
Intensity32a
1/16 (min on)
0x15
0
000
0
Intensity54a
1/16 (min on)
0x16
0
000
0
Intensity76a
1/16 (min on)
0x17
0
000
0
Digit 0
Blank digit, both planes
0x60
0
010
000
0
Digit 1
Blank digit, both planes
0x61
0
010
000
0
Digit 2
Blank digit, both planes
0x62
0
010
000
0
Digit 3
Blank digit, both planes
0x63
0
010
000
0
Digit 4
Blank digit, both planes
0x64
0
010
000
0
Digit 5
Blank digit, both planes
0x65
0
010
000
0
Digit 6
Blank digit, both planes
0x66
0
010
000
0
Digit 7
Blank digit, both planes
0x67
0
010
000
0
Digit 0a
Blank digit, both planes
0x68
0
000
0
Digit 1a
Blank digit, both planes
0x69
0
000
0
Digit 2a
Blank digit, both planes
0x6A
0
000
0
Digit 3a
Blank digit, both planes
0x6B
0
000
0
Digit 4a
Blank digit, both planes
0x6C
0
000
0
Digit 5a
Blank digit, both planes
0x6D
0
000
0
Digit 6a
Blank digit, both planes
0x6E
0
000
0
Digit 7a
Blank digit, both planes
0x6F
0
000
0
Key_A Debounced
No key presses have been detected
0x88
0
000
0
Key_B Debounced
No key presses have been detected
0x89
0
000
0
Key_C Debounced
No key presses have been detected
0x8A
0
000
0
Key_D Debounced
No key presses have been detected
0x8B
0
000
0
Key_A Pressed
Keys are not pressed
0x8C
0
000
0
Key_B Pressed
Keys are not pressed
0x8D
0
000
0
Key_C Pressed
Keys are not pressed
0x8E
0
000
0
Key_D Pressed
Keys are not pressed
0x8F
0
000
0
Table 15. Initial Power-Up Register Status