CHAPTER 13 SERIAL ARRAY UNIT
User’s Manual U19678EJ1V1UD
615
Figure 13-5. Format of Serial Clock Select Register 0 (SPS0)
Address: F0126H, F0127H (SPS0), F0166H, F0167H (SPS1)
After reset: 0000H
R/W
Symbol
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
SPS0
0
PRS
013
PRS
012
PRS
011
PRS
010
PRS
003
PRS
002
PRS
001
PRS
000
Section of operation clock (CK0k)
Note 1
PRS
0k3
PRS
0k2
PRS
0k1
PRS
0k0
fCLK = 2 MHz
fCLK = 5 MHz
fCLK = 10 MHz
fCLK = 20 MHz
0
fCLK
2 MHz
5 MHz
10 MHz
20 MHz
0
1
fCLK/2
1 MHz
2.5 MHz
5 MHz
10 MHz
0
1
0
fCLK/2
2
500 kHz
1.25 MHz
2.5 MHz
5 MHz
0
1
fCLK/2
3
250 kHz
625 kHz
1.25 MHz
2.5 MHz
0
1
0
fCLK/2
4
125 kHz
313 kHz
625 kHz
1.25 MHz
0
1
0
1
fCLK/2
5
62.5 kHz
156 kHz
313 kHz
625 kHz
0
1
0
fCLK/2
6
31.3 kHz
78.1 kHz
156 kHz
313 kHz
0
1
fCLK/2
7
15.6 kHz
39.1 kHz
78.1 kHz
156 kHz
1
0
fCLK/2
8
7.81 kHz
19.5 kHz
39.1 kHz
78.1 kHz
1
0
1
fCLK/2
9
3.91 kHz
9.77 kHz
19.5 kHz
39.1 kHz
1
0
1
0
fCLK/2
10
1.95 kHz
4.88 kHz
9.77 kHz
19.5 kHz
1
0
1
fCLK/2
11
977 Hz
2.44 kHz
4.88 kHz
9.77 kHz
1
INTTM02
Note 2
Other than above
Setting prohibited
Notes 1. When changing the clock selected for fCLK (by changing the system clock control register (CKC)
value), do so after having stopped (serial channel stop register 0 (ST0) = 000FH) the operation of the
serial array unit (SAU). When selecting INTTM02 for the operation clock, also stop the timer array
unit TAUS (timer channel stop register 0 (TT0) = 00FFH).
2. SAU can be operated at a fixed division ratio of the subsystem clock, regardless of the fCLK frequency
(main system clock, sub system clock), by operating the interval timer for which fSUB/4 has been
selected as the count clock (setting TIS02 bit of the timer input select register 0 (TIS0) to 1) and
selecting INTTM02 by using the SPS0 register in channel 2 of TAUS. When changing fCLK, however,
SAU and TAUS must be stopped as described in Note 1 above.
Cautions 1. Be sure to clear bits 15 to 8 to “0”.
2. After setting bit 2 (SAU0EN) of the PER0 register to 1, be sure to set serial clock select
register 0 (SPS0) after 4 or more fCLK clocks have elapsed.
Remarks 1. fCLK: CPU/peripheral hardware clock frequency
fSUB: Subsystem clock frequency
2. k = 0, 1