R01UH0823EJ0100 Rev.1.00
Page 1667 of 1823
Jul 31, 2019
RX23W Group
50. Flash Memory (FLASH)
SAS[1:0] Bits (Start-Up Area Select)
These bits are used to select the start-up area. To change the start-up area, the following three methods can be used.
(1) When selecting the start-up area according to the start-up area settings of the extra area
With the SAS[1:0] bits set to 00b or 01b, the start-up area is selected according to the start-up area settings of the extra
area. The settings are enabled after a reset is released.
(2) When switching the start-up area to the default area temporarily
When 10b is written to the SAS[1:0] bits, the start-up area is switched to the default area immediately after data is written
to the register, regardless of the start-up area settings of the extra area.
When a reset is generated after this, the area is selected according to the start-up area settings of the extra area.
(3) When switching the start-up area to the alternative area temporarily
When 11b is written to the SAS[1:0] bits, the start-up area is switched to the alternative area, regardless of the start-up
area settings of the extra area.
When a reset is generated after this, the area is selected according to the start-up area settings of the extra area.
Table 50.3
Example of FlashIF Clock Frequency Settings
FlashIF Clock
Frequency (MHz)
PCKA[4:0] Bit
Setting
FlashIF Clock
Frequency (MHz)
PCKA[4:0] Bit
Setting
FlashIF Clock
Frequency (MHz)
PCKA[4:0] Bit
Setting
32
11111b
31
11110b
30
11101b
29
11100b
28
11011b
27
11010b
26
11001b
25
11000b
24
10111b
23
10110b
22
10101b
21
10100b
20
10011b
19
10010b
18
10001b
17
10000b
16
01111b
15
01110b
14
01101b
13
01100b
12
01011b
11
01010b
10
01001b
9
01000b
8
00111b
7
00110b
6
00101b
5
00100b
4
00011b
3
00010b
2
00001b
1
00000b
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