W681308DG Datasheet, PDF (22/64 Pages) Nuvotem Talema – W681308 USB Audio Controller from Nuvoton integrates fast 8051 Microcontroller Unit (MCU)

W681308
XXXX PRODUCT DESCRIPTION
8.2.3
Special Function Registers (SFR)
Address
F8
F0
E8
E0
D8
D0
C8
C0
B8
B0
A8
A0
98
90
88
80
Byte 0
EIP
B
EIE
ACC
WDCON
PSW
T2CON
IP
P3
IE
P2
SCON
P1
TCON
P0
Byte 1
T2MOD
SADEN
SADDR
XRAMAH
SBUF
TMOD
SP
Byte 2
Byte 3
Byte 4
Byte 5
Byte 6
RCAP2L
RCAP2H
TL2
PMR
TH2
STATUS
TL0
TL1
TH0
TH1
CKCON
DPL
DPH
DPL1
DPH1
DPS
Byte 7
TA
PCON
Table 2 W681308 MCU SFR location
8.3
Power Management
The W681308 has IDLE mode operation features that manage and save power consumption of the device.
Enable IDLE mode
The user can set the device into idle mode by writing 1 to the PCON bit of SFR. The instruction that sets the idle bit is the last
instruction that will be executed before the device goes into Idle Mode. In the Idle mode, the clock to the MCU is halted but
not to the Interrupt, Timer, Watchdog timer, and Serial ports blocks. This forces the MCU state to be frozen; the Program
counter, the Stack Pointer, the Program Status Word, the Accumulator and the other registers hold their contents. The ALE
and PSEN pins are held high during the idle state. The port pins hold the logical states they had at the time Idle was
activated.
The Idle mode can be terminated in two ways:
ƒ Activation of any enabled interrupt
Since the interrupt controller is still active, the activation of any enabled interrupt can wake up the processor. This will
automatically clear the Idle bit, terminate the Idle mode, and the Interrupt Service Routine (ISR) will be executed. After the
ISR, execution of the program will continue from the instruction which put the device into idle mode.
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Rev1.2