SH61F83
23
5.4. Wake-up Timer
The SH61F83 has a Built-in 32KHz Ring-Oscillator. It is the clock source of wake-up timer. The 32KHz Ring-Oscillator will
start when the control register
WKT[3:2]
was not equal to #00b.
The wake-up timer can only be enabled/disabled by
WKT[3:0]
(
WKT[3:0]
not equal to 00xxb).
If the Wake-up timer is enabled and system enter idle/power-down mode, the wake-up timer will load the time-out period
register
WKT[3:0]
and start to count.
0095H
WKT_CON Initial Value
Wake-up Timer & Resume Reset Control Register
Bit[7:6]
-
00b
-
Reserved
Bit[5:4]
Period
[1:0]
10b
R/W
Internal Resume Reset period for Power-Down mode
(these times do
not include resonator start-up time)
00: 2
10
T
SYS
(170us)
01: 2
11
T
SYS
(340us)
10: 2
16
T
SYS
(10.922ms)
11: 2
17
T
SYS
(21.845ms)
Reset source: Hardware reset
Bit[3:0]
WKT[3:0]
0000b
R/W
Wake-up timer
00xx: disable Wake-up timer under
Power-down mode
or
IDLE mode
Others: enable Wake-up timer under
Power-down mode
or
IDLE mode
0101: 2
0
T
RING
(31.25us@32KHz)
0110: 2
7
T
RING
(4ms@32KHz)
0111: 2
8
T
RING
(8ms@32KHz)
0100: 2
9
T
RING
(16ms@32KHz)
1001: 2
10
T
RING
(32ms@32KHz)
1010: 2
11
T
RING
(64ms@32KHz)
1011: 2
12
T
RING
(128ms@32KHz)
1000: 2
13
T
RING
(256ms@32KHz)
1101: 2
14
T
RING
(512ms@32KHz)
1110: 2
15
T
RING
(1.024s@32KHz)
1111: 2
16
T
RING
(2.048s@32KHz)
1100: 2
17
T
RING
(4.096s@32KHz)
Reset source: Hardware reset
5.5 MODE_FG Flag
0096H MODE_FG Initial Value
Mode Register
Bit7
-
0b
-
Reserved
Bit6
Nonidle
0b
R/W
USB bus flag. Write “0” to clear, write “1” no effect.
1: set by non-idle event
Reset source: Hardware reset, USB reset
Bit5
WKUPT
0b
R/W
Set “1” after wake-up timer time-out. Write “0” to clear, write “1” no effect.
Reset source: Hardware reset or USB reset
Bit4
RES_TRG
0b
R/W
“1”: Remote wake up; “0”: Global wake up.
Write “0” to clear, write “1” no effect.
Reset source: Hardware reset or USB reset
Bit3
WDT
0b
R/W
Set “1” after Watchdog reset. Write “0” to clear, write “1” no effect.
Reset source: Hardware reset or USB reset
Bit2
USBRST
0b
R/W
Set “1” after USB reset. Write “0” to clear, write “1” no effect.
Reset source: Hardware reset
Bit1
POF
1b
R/W
Set “1” after power-on reset, Low voltage reset and External reset.
Write “0” to clear, write “1” no effect.
Reset source: Hardware reset
Bit0
SUSF
0b
R/W
Set “1” when entering Power-down mode.
Write “0” to clear, write “1” no effect.
Reset source: Hardware reset or USB reset
