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AS1115

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

The Shutdown Register controls AS1115 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 Register corresponds to its respective display digit (i.e., bit D0 corresponds to digit 0,

bit D1 corresponds to digit 1 and so on). Table 9 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 9 lists the

code-B font; Table 10 lists the HEX font.

When no-decode mode is selected, data bits D7:D0 of the Digit-Registers correspond to the segment lines of the AS1115. Table 11 shows the

1:1 pairing of each data bit to the appropriate segment line.

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

0

1

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

KEYA

000

1

1

1

0

0

KEYB

000

1

1

1

0

1

Table 7. 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

X

X

X

X

X

X

0

Shutdown Mode, Feature Register Unchanged

0x80

1

X

X

X

X

X

X

0

Normal Operation,

Reset Feature Register to Default Settings

0x01

0

X

X

X

X

X

X

1

Normal Operation, Feature Register Unchanged

0x81

1

X

X

X

X

X

X

1

Table 8. Decode Enable Register Format Examples

Decode Mode

HEX Code

Register Data

D7

D6

D5

D4

D3

D2

D1

D0

No decode for digits 7:0

0x00

0

0

0

0

0

0

0

0

Code-B/HEX decode for digit 0. No decode for digits 7:1

0x01

0

0

0

0

0

0

0

1

Code-B/HEX decode for digit 0:2. No decode for digits 7:3

0x07

0

0

0

0

0

1

1

1

Code-B/HEX decode for digits 0:5. No decode for digits 7:6

0x3F

0

0

1

1

1

1

1

1

Code-B/HEX decode for digits 0,2,5.

No decode for digits 1, 3, 4, 6, 7

0x25

0

0

1

0

0

1

0

1

Table 6. Register Address Map

Register

Address

Page

D15:D13

D12

D11

D10

D9

D8

D7:D0