SPI Driver for Enhanced Relay Control

TLE7238SL

Serial Peripheral Interface (SPI)

Data Sheet

29

Rev. 1.0, 2010-02-18

Figure 11

Data Transfer in Daisy Chain Configuration

9.3

SPI Protocol

The control and diagnosis function of the TLE7238SL is based on two register banks which are accessed via

following SPI protocol. The control register bank contains eight registers (with 4 bit each) addressed by a 3 bit

pointer. The diagnosis register bank contains four registers (with 4 bit each) addressed by a 2 bit pointer. An

additional indication bit is available to differentiate between standard diagnosis information and data read from a

register bank.

Control and Diagnosis Mode

Note: Reading a register needs two SPI frames. In the first frame the RD command is sent. In the second frame,

the output at SPI signal SO will contain the requested information. Any command can be executed in the

second frame.

1) This bit is valid between CS hi -> lo and first SCLK lo -> hi transition.

76

543

210

Write Register Command

SI

1

ADDR

DATA

Read Register Command

SI

0

ADDR

x

x

0

RB

Read Standard Diagnosis

SI

0x

x

x

x

x

1x

Standard Diagnosis

S

O

TER

0

AWK

LH

D67

D45

D23

D01

Second Frame of Read Command

S

O

TER

0

1

ADDR (Diagnosis)

DATA

S

O

TER

1

ADDR (Control)

DATA

MI

MO

MCS

MCLK

SI device 3

SI device 2

SI device 1

SO device 3

SO device 2

SO device 1

time

SPI_DasyChain2.emf