w681308 Winbond Electronics Corp America, w681308 Datasheet - Page 22

• Manufacturer Part Number: w681308
• Description: Usb Audio Controller
• Manufacturer: Winbond Electronics Corp America

8.2.3
8.3
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:
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.
Address
Activation of any enabled interrupt
E8
E0
D8
D0
C8
C0
B8
B0
A8
A0
F8
F0
98
90
88
80
Power Management
Special Function Registers (SFR)
WDCON
T2CON
SCON
Byte 0
TCON
PSW
ACC
EIP
EIE
P3
P2
P1
P0
IP
IE
B
XRAMAH
T2MOD
SADDR
SADEN
TMOD
SBUF
Byte 1
SP
Table 2 W681308 MCU SFR location
RCAP2L
DPL
Byte 2
TL0
XXXX PRODUCT DESCRIPTION
RCAP2H
22
Byte 3
DPH
TL1
Byte 4
DPL1
PMR
TH0
TL2
STATUS
Byte 5
DPH1
TH2
TH1
CKCON
Byte 6
DPS
W681308
Rev1.2
Byte 7
PCON
TA