PC87365 datasheet(84/215 Pages) NSC

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3.0 System Wake-Up Control (SWC) (Continued)

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To enable the IRQ of a specific logical device to trigger a wake-up event, the associated Enable bit must be set to 1. This is

bit 4 of the Interrupt Number and Wake-Up on IRQ Enable register, located at index 70h in the configuration space of the

logical device (see Table 10 in

Device Architecture and Configuration chapter). When this bit is set, any IRQ assertion of the

corresponding logical device activates the module IRQ wake-up event. Therefore, the module IRQ wake-up event is a com-

bination of all IRQ signals of the logical devices for which wake-up on IRQ is enabled.

Note that index 70h has two functions: it is used to set IRQ and to enable wake-up on IRQ. If the BIOS routine that sets IRQ

does not use a Read-Modify-Write sequence, it might reset bit 4, which is the Wake-Up on IRQ bit. To ensure that the system

wakes up, the BIOS must set bit 4 before the system goes to sleep.

When the event is detected as active, its associated Status bit (bit 7 of the WK0_STS register) is set to 1. If the associated

Enable bit (bit 7 of the WK_EN0 register) is also set to 1, the PWUREQ output is asserted. It remains asserted until the Status

bit is cleared.

Since all the logical devices listed above are powered by VDD, a module IRQ event can be activated only when VDD is

present.

3.4

SWC REGISTERS

The SWC registers are organized in four banks, all of which are battery-backed. The offsets are related to a base address

that is determined by the SWC Base Address register in the device configuration registers. The lower 19 offsets are common

to the four banks, while the upper offsets (13-1fh) are divided as follows:

Bank 0 holds the Keyboard/Mouse Control registers.

Bank 1 holds the CEIR Control registers.

Bank 2 holds the Event Routing Conﬁguration and Wake-Up Extension Control registers.

Bank 3 holds the Standby General-Purpose I/O (GPIO) Pins Conﬁguration registers.

The active bank is selected through the Configuration Bank Select field (bits 1-0) in the Wake-Up Configuration register

(WK_CFG). See Section 3.4.6.

As a programming aid, the registers are described in this chapter according to the following functional groupings:

General status, enable, conﬁguration and routing registers.

Extension enable registers.

PS/2 event conﬁguration registers.

CEIR event conﬁguration registers.

Standby GPIO conﬁguration and control registers.

The following abbreviations are used to indicate the Register Type:

R/W = Read/Write.

R = Read from a speciﬁc address returns the value of a speciﬁc register. Write to the same address is to a different

W = Write.

RO = Read Only.

R/W1C = Read/Write 1 to Clear. Writing 1 to a bit clears it to 0. Writing 0 has no effect.

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