NEC uPD78P078 User Manual
Page 421
421
CHAPTER 19 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 19-5. 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 to ADTI during operation of the automatic data transmit/receive function.
2.
Bits 5 and 6 must be set to 0.
3.
When controlling the data transfer interval by automatic transmit/receive using ADTI, busy
control (refer to 19.4.3 (4) (a) Busy control option) becomes invalid.
Remark
f
XX
: Main system clock frequency (f
X
or f
X
/2)
f
X
: Main system clock oscillation frequency
f
SCK
: Serial clock frequency
2
6
28
0.5
f
XX
2
6
36
1.5
f
XX
f
XX
f
SCK
f
XX
f
SCK
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