NEC uPD78056Y User Manual

Page 401

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401

CHAPTER 18 SERIAL INTERFACE CHANNEL 1

(4) Automatic data transmit/receive interval specify register (ADTI)

This register sets the automatic data transmit/receive function data transfer interval.

ADTI is set by a 1-bit or 8-bit memory manipulation instruction.

RESET input sets ADTI to 00H.

Figure 18-5. Automatic Data Transmit/Receive Interval Specify Register Format (1/4)

Notes 1. The interval is dependent only on CPU processing.

2. The data transfer interval includes an error. The data transfer minimum and maximum intervals are

found from the following expressions (n: Value set in ADTI0 to ADTI4). However, if a minimum which

is calculated by the following expressions is smaller than 2/f

SCK

, the minimum interval time is 2/f

SCK

.

Minimum = (n+1)

×

+

+

, Maximum = (n+1)

×

+

+

Cautions 1.

Do not write ADTI during operation of automatic data transmit/receive function.

2.

Bits 5 and 6 must be set to zero.

3.

To control the data transfer interval by means of automatic transmission/reception with

ADTI, busy control (refer to 18.4.3 (4) (a) Busy control option) is disabled.

Remarks 1. f

XX

: Main system clock frequency (f

X

or f

X

/2)

2. f

X

: Main system clock oscillation frequency

3. f

SCK

: Serial clock frequency

2

6

36

2

6

28

0.5

f

XX

f

XX

f

SCK

1.5

f

SCK

f

XX

f

XX

Data Transfer Interval Specification (f

XX

= 5.0 MHz Operation)

ADTI4 ADTI3 ADTI2 ADTI1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

1

1

1

1

1

1

1

1

0

0

0

0

1

1

1

1

0

0

0

0

1

1

1

1

0

0

1

1

0

0

1

1

0

0

1

1

0

0

1

1

Minimum

Note 2

18.4

s + 0.5/f

SCK

31.2

s + 0.5/f

SCK

44.0

s + 0.5/f

SCK

56.8

s + 0.5/f

SCK

69.6

s + 0.5/f

SCK

82.4

s + 0.5/f

SCK

95.2

s + 0.5/f

SCK

108.0

s + 0.5/f

SCK

120.8

s + 0.5/f

SCK

133.6

s + 0.5/f

SCK

146.4

s + 0.5/f

SCK

159.2

s + 0.5/f

SCK

172.0

s + 0.5/f

SCK

184.8

s + 0.5/f

SCK

197.6

s + 0.5/f

SCK

210.4

s + 0.5/f

SCK

Maximum

Note 2

20.0

s + 1.5/f

SCK

32.8

s + 1.5/f

SCK

45.6

s + 1.5/f

SCK

58.4

s + 1.5/f

SCK

71.2

s + 1.5/f

SCK

84.0

s + 1.5/f

SCK

96.8

s + 1.5/f

SCK

109.6

s + 1.5/f

SCK

122.4

s + 1.5/f

SCK

135.2

s + 1.5/f

SCK

148.0

s + 1.5/f

SCK

160.8

s + 1.5/f

SCK

173.6

s + 1.5/f

SCK

186.4

s + 1.5/f

SCK

199.2

s + 1.5/f

SCK

212.0

s + 1.5/f

SCK

6

5

4

3

2

1

0

7

Symbol

ADTI ADTI7

0

0

ADTI4 ADTI3 ADTI2 ADTI1 ADTI0

FF6BH 00H R/W

Address After Reset R/W

ADTI7

0

Data Transfer Interval Control

No control of interval by ADTI

Note 1

Control of interval by ADTI (ADTI0 to ADTI4)

1

ADTI0

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

µ

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