LifecyclePhase:

Revision

: 2

Expired Period: Forever

Release Date:2013-06-04 08:06:07.0

DATASHEET

ALS-PDIC17-57B/TR8

9

Copyright © 2010, Everlight All Rights Reserved. Release Date : 5.27.2013. Issue No: DLS-0000049

Rev.2

www.everlight.com

Communication Protocol

ALS-PDIC17-57B contains an 8-bit command register that can be written and read via the I

register controls the overall operation of the device. There is a two-byte word read-only register that contains the latest

converted value of A/D converter. The I

All the Send Byte protocol, the Receive Byte protocol and Receive Word protocol are implemented in ALS-PDIC17-57B.

The Send Byte protocol allows single bytes of data to be written to the device (see Figure 13-a). The written byte is

called the COMMAND byte. The Receive Byte protocol allows one-byte data to be read from the device (see Figure 13-b).

Two-byte data can be read by following the Receive Word Protocol shown in Figure 13-c. In Figure 13, the clear area

represents data sent by the host (master) and the shaded area represents data returned by the ambient light sensor (slave

device).

1

7

1

1

8

1

1

S

Slave Address

WR

A

Command Byte

A

P

0

0

0

(a) Send byte protocol

1

7

1

1

8

1

1

S

Slave Address

RD

A

Data

NA

P

1

0

1

(b) Receive byte protocol

1

7

1

1

8

1

8

1

1

S

Slave Address

RD

A

LS byte of ADC

A

MS byte of ADC

NA

P

1

0

0

1

(c) Receive word (two bytes) protocol

S

= start condition

P

= stop condition

Shaded

= slave transmission

A

= acknowledge

NA

= not acknowledge

WR

= write

RD

= read

Figure 13 Communication Protocol