ICS1531 datasheet(65/76 Pages) ICST

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Chapter 10

Timing Diagrams

ICS1531 Rev N 12/1/99

December, 1999

ICS1531 Data Sheet - Preliminary

10.1.3

Acknowledge Conditions

Figure 10-3 shows in general how an acknowledge works on an industry-standard 2-wire serial bus.

• For start and stop conditions, see Section 10.1.1, “Start and Stop Conditions”.

• The data transfers (1). (For details, see Section 10.1.2, “Transfer of Data Bytes”.) If there is a:

– Data read, the ICS1531 drives the data, and the master (typically, a microcontroller) drives the ACK.

– Data write, the master drives the data, and the ICS1531 drives the ACK.

• The acknowledge bit (ACK) is the ninth (and last) bit output.

– The ACK bit is a read-write bit that indicates whether the first 8 bits are either:

• Read from the ICS1531 by a master device (typically, a microcontroller), or

• Written to the ICS1531 by a master device

– For an acknowledge (2) to occur, you must do the following:

• Address the ICS1531 properly

• Write a valid register index

• Read/write the specified data

Figure 10-3.

Acknowledge on Industry-Standard 2-Wire Serial Bus

Clock from

Master Device

Clock

Pulse 1

Data Signal

Bit 6

(2)

ACK

Bit 7

(MSB)

Bit 0

(LSB)

Acknowledge

Clock Pulse

Data Transfer

Acknowledge

(1)

ICS1531 Datasheet(PDF) 65 Page - Integrated Circuit Systems