P R E L I M I N A R Y

AMD

 

 

 

 

 

 

 

 

When written with a 1, the PWRDWN bit generates an interrupt to

 

 

 

the 80188, requesting that the 80188 core place the Am79C930 de-

 

 

 

vice into the power down state. The interrupt is signaled in MIR0, bit

 

 

 

5. If written with a 0 while in power down mode, power down mode is

 

 

 

exited. When written with a 1, value read will remain 0 until the de-

 

 

 

vice actually enters the power down mode.

 

 

1

Interrupt

Represents the internal interrupt level. This signal remains true un-

 

 

 

til the interrupt has been serviced (not pulse generated).

0

Reserved

Read only as a 0.

 

 

PCMCIA Card Information Structure (CIS)

The PCMCIA CIS space has been allocated to reside in the flash memory space of a design based on the Am79C930 device. This space corresponds to 1K–16 bytes of the uppermost 1K of flash memory. Since only even addressed bytes of attribute memory space are defined to exist in the PCMCIA specification, only even addresses of the 2K–32 CIS range will map into the flash memory, and hence, the 2K–32 address range for the Am79C930 CIS space is mapped to only 1K–16 bytes of flash space.

Note that the address range is limited to 2K–32 rather than a complete 2K of space. This is because the upper- most 16 bytes of the flash memory must be reserved for the initial instructions for the 80188 core, since the 80188 core will automatically access these locations for its initial instruction fetch following a Am79C930 device reset operation.

Am79C930

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Image 125
AMD Am79C930 Vice actually enters the power down mode Interrupt, Til the interrupt has been serviced not pulse generated