CHAPTER 5. PERIPHERAL HARDWARE FUNCTIONS

Fig. 5-45 ACKE Operation

(a) When ACKE = 1 on completion of transfer

SCK

1

2

 

7

8

9

 

 

 

 

 

 

 

 

ACK signal is output in 9th

SB0

D7

D6

D2

D1

D0

ACK

clock cycle.

 

ACKE

When ACKE = 1 at this point

(b) When ACKE is set after completion of transfer

SCK

6

7

8

9

SB0

 

D2 D1

D0

 

ACKE

ACK

ACK signal is output in 1 clock interval immediately after ACKE is set.

When ACKE is set in this interval and ACKE = 1 on next fall of SCK

(c)When ACKE = 0 on completion of transfer

SCK

1

2

7

8

SCK

D7

D6

D2 D1

D0

ACKE

9

ACK signal is not output.

When ACKE = 0 at this point

(d) When ACKE = 1 interval is short

SCK

SB0

D2 D1 D0

ACK signal is not output.

ACKE

When ACKE is set and cleared in this interval and

ACKE = 0 on next fall of SCK

108

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NEC PD75402A When Acke is set after completion of transfer, When Acke = 0 on completion of transfer, 108, Acke ACK