L5953

18/24

Figure 16. Write the Status Register (after a Write Enable Latch Sequence, operation A)

Figure 17. Read the Status Register

IRQ - Interrupt Request Pin

s

It is an open drain pin activated (low) every time a variation occurs in the Diagnostic Register.

s

Purpose: to alert the

µP that one or more warning bit of the Diagnostic Register has changed from 0 to

1 or from 1 to 0.

s

An activation of this pin puts the bit s0 of the Status Register to 1 (START DIAGNOSTIC) like an

Operation E (Diagnostic Procedure Start). Then an Operation F has to be executed without an

Operation E before.

s

After an Operation F, the IRQ pin is disactivated, and goes to 1 if connected to a pull-up resistor.

L5953 - Application Note

00

01

02

03

04

HIGH IMPEDANCE

INSTRUCTION

STATUS REGISTER

05

06

07

08

09

10

11

12

13

14

15

16

17

18

19

20

21

22

23

s15

s14

s13

s12

s11

s10

s9

s8

s7

s6

s5

s4

s3

s2

s1

s0

S

C

D

Q

D03AU1488

CPOL=0, CPHA=0

00

01

02

03

04

HIGH IMPEDANCE

INSTRUCTION

STATUS REGISTER OUT

05

06

07

08

09

10

11

12

13

14

15

S

C

D

Q

D03AU1489

16

17

18

19

20

21

22

23

s15

s14

s13

s12

s11

s10

s9

s8

s7

s6

s5

s4

s3

s2

s1

s0

CPOL=0, CPHA=0