NEC Network Controller uPD98502 - Manual (Page 199)

CHAPTER 3 SYSTEM CONTROLLER
Preliminary User’s Manual S15543EJ1V0UM 199
3.2.12 S_PWCR (Power Control Register)
The power control register “S_PWCR” is a read-write and 32-bit word-aligned register. S_PWCR requests to keep
the idle state for USB Controller, Ethernet Controller, ATM Cell Processor, and PCI Controller by setting following
IDRQ fields. V
R
4120A must request these blocks to keep the idle state and check their acknowledgement by reading
the power status register “S_PWSR” prior to perform suspend by setting following STOP fields. S_PWCR is initialized
to 0 at reset and contains the following fields:
Bits Field R/W Default Description
31:22 Reserved R/W 0 Hardwired to 0.
21 PCISTOP R/W 0 Suspend request for PCI Controller:
0 = enable system clock for PCI Controller.
1 = disable system clock for PCI Controller.
20 Reserved R/W 0 Hardwired to 0.
19 MAC2STOP R/W 0 Suspend request for Ethernet Controller #2:
0 = enable system clock for Ethernet Controller #2.
1 = disable system clock for Ethernet Controller #2.
18 ATMSTOP R/W 0 Suspend request for ATM Cell Processor:
0 = enable system clock for ATM Cell Processor.
1 = disable system clock for ATM Cell Processor.
17 MACSTOP R/W 0 Suspend request for Ethernet Controller #1:
0 = enable system clock for Ethernet Controller #1.
1 = disable system clock for Ethernet Controller #1.
16 USBSTOP R/W 0 Suspend request for USB Controller:
0 = enable system clock for USB Controller.
1 = disable system clock for USB Controller.
15:6 Reserved R/W 0 Hardwired to 0.
5 PCIIDRQ R/W 0 Idle request for PCI Controller:
0 = do nothing.
1 = request to keep the idle state.
4 Reserved R/W 0 Hardwired to 0.
3 MAC2IDRQ R/W 0 Idle request for Ethernet Controller #2:
0 = do nothing.
1 = request to keep the idle state.
2 ATMIDRQ R/W 0 Idle request for ATM Cell Processor:
0 = do nothing.
1 = request to keep the idle state.
1 MACIDRQ R/W 0 Idle request for Ethernet Controller #1:
0 = do nothing.
1 = request to keep the idle state.
0 USBIDRQ R/W 0 Idle request for USB Controller:
0 = do nothing.
1 = request to keep the idle state.
Remark Before accesses to this register, the V R 4120A must flush the internal write command buffer by reading the
IBUS target.