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CHAPTER 3 SYSTEM CONTROLLER
Preliminary User’s Manual S14767EJ1V0UM00
235
3.2.2.11 Power Control Register (S_PWCR)
The Power Control Register “S_PWCR” is read-write and word aligned 32bit register. S_PWCR requests to keep
the IDLE State for USB Controller, Ethernet Controller, and ATM Cell Processor. CPU must request these interface
block to keep the IDLE State and check their acknowledgement using read the Power Status Register “S_PWSR”
prior to perform SUSPEND by setting following xxxSTOP field. S_WRCR is initialized to 0 at reset and contains the
following fields:
Bits
Field
Description
0
USBIDRQ
IDLE request for USB Controller:
0 = do nothing.
1 = request to keep the IDLE State.
1
MACIDRQ
IDLE request for Ethernet Controller #1:
0 = do nothing.
1 = request to keep the IDLE State.
2
ATMIDRQ
IDLE request for ATM Cell Processor:
0 = do nothing.
1 = request to keep the IDEL State.
3
MAC2IDRQ
IDLE request for Ethernet Controller #2:
0 = do nothing.
1 = request to keep the IDEL State.
15:4
Reserved
Hardwired to 0.
16
USBSTOP
SUSPEND request for USB Controller:
0 = enable system clock for USB Controller.
1 = disable system clock for USB Controller.
17
MACSTOP
SUSPEND request for Ethernet Controller #1:
0 = enable system clock for Ethernet Controller #1.
1 = disable system clock for Ethernet Controller #1.
18
ATMSTOP
SUSPEND request for ATM Cell Processor:
0 = enable system clock for ATM Cell Processor.
1 = disable system clock for ATM Cell Processor.
19
MAC2STOP
SUSPEND request for Ethernet Controller #2:
0 = enable system clock for Ethernet Controller #2.
1 = disable system clock for Ethernet Controller #2.
31:20
Reserved
Hardwired to 0.
Remark
Before accesses to this register, the CPU must flush the internal write command buffer by reading the IBUS
target