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AS1117

Datasheet - D e t a i l e d D e s c r i p t i o n

The Shutdown Register controls AS1117 shutdown mode.

Decode Enable Register (0x09)

The Decode Enable Register sets the decode mode. BCD/HEX decoding (either BCD code – characters 0:9, E, H, L,

P, and -, or HEX code – characters 0:9 and A:F) is selected by bit D2 (page 18) of the Feature Register. The Decode

Enable Register is used to select the decode mode or no-decode for each digit. Each bit in the Decode Enable Regis-

ter corresponds to its respective display digit (i.e., bit D0 corresponds to digit 0, bit D1 corresponds to digit 1 and so

on). Table 10 on page 14 lists some examples of the possible settings for the Decode Enable Register bits.

Note:

A logic high enables decoding and a logic low bypasses the decoder altogether.

When decode mode is used, the decoder looks only at the lower-nibble (bits D3:D0) of the data in the Digit-Registers,

disregarding bits D6:D4. Bit D7 sets the decimal point (SEG DP) independent of the decoder and is positive logic (bit

D7 = 1 turns the decimal point on). Table 10 on page 14 lists the code-B font; Table 11 on page 14 lists the HEX font.

Decode-Mode

000

0

1

0

0

1

(see Table 9 on page 14)

13

Global Intensity

000

0

1

0

1

0

(see Table 18 on page 17)

17

Scan Limit

000

0

1

0

1

1

(see Table 20 on page 17)

17

Shutdown

000

0

1

1

0

0

(see Table 8 on page 13)

12

Self-Adressing

001

0

1

1

0

1

N/A

Feature

000

0

1

1

1

0

(see Table 21 on page 18)

18

Display Test Mode

000

0

1

1

1

1

(see Table 15 on page 16)

14

DIG0:DIG1 Intensity

000

1

0

0

0

0

(see Table 19 on page 17)

DIG2:DIG3 Intensity

000

1

0

0

0

1

(see Table 19 on page 17)

DIG4:DIG5 Intensity

000

1

0

0

1

0

(see Table 19 on page 17)

DIG6:DIG7 Intensity

000

1

0

0

1

1

(see Table 19 on page 17)

Diagnostic Digit 0

000

1

0

1

0

0

N/A

Diagnostic Digit 1

000

1

0

1

0

1

N/A

Diagnostic Digit 2

000

1

0

1

1

0

N/A

Diagnostic Digit 3

000

1

1

0

1

1

N/A

Diagnostic Digit 4

000

1

1

0

0

0

N/A

Diagnostic Digit 5

000

1

1

0

0

1

N/A

Diagnostic Digit 6

000

1

1

0

1

0

N/A

Diagnostic Digit 7

000

1

1

0

1

1

N/A

KEY

000

1

1

1

0

0

Table 8. Shutdown Register Format (Address (HEX) = 0x0C))

Mode

HEX Code

Register Data

D7

D6

D5

D4

D3

D2

D1

D0

Shutdown Mode,

Reset Feature Register to Default Settings

0x00

0

XXXXXX

0

Shutdown Mode, Feature Register Unchanged

0x80

1

XXXXXX

0

Normal Operation,

Reset Feature Register to Default Settings

0x01

0

XXXXXX

1

Normal Operation, Feature Register Unchanged

0x81

1

XXXXXX

1

Table 7. Register Address Map

Register

Address

Page

D15:D13

D12

D11

D10

D9

D8

D7:D0