Acer 390 Series, Service Manual

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2-10 Service Guide
Table 2-2 PCI1250 Terminal Functions
Name No. I/O Type Function
BVD2
(SPKR) Y05 D10 I Battery Voltage Detect 2. Generated by 16-bit
memory PC Cards that include batteries. BVD2 is
used with BVD1 as an indication of the condition of
the batteries on a memory PC Card. Both BVD1
and BVD2 are high when the battery is good. When
BVD2 is low and BVD1 is high, the battery is weak
and needs to be replaced. When BVD1 is low, the
battery is no longer serviceable and the data in the
memory PC Card is lost. See the Card Status
Change Interrupt Configuration Register for enable
bits. See the Card Status Change register and the
Interface Status register for the status bits for this
signal.
Speaker (SPKR) Speaker is an optional binary
audio signal available only when the card and
socket have been configured: for the 16-bit l/O
interface. The audio signals from cards A and B are
combined by the PCI 1250A and are output on the
SPKROUT pin.
DMA Request.: This pin may be used as the DMA
request signal during DMA operations to a 16-bit
PC Card that supports DMA. The PC Card asserts
this signal to indicate a request for a DMA
operation.
CD1
CD2 G03
W06 H20
C09 I PC Card Detect 1 and Card Detect 2. CD1 and CD2
are connected to ground internally on the PC Card.
When a PC Card is inserted into a socket. these
signals are pulled low. The signal status is available
by reading the interface status register
CE1
CE2 K01
L02 D20
D19 O Card Enable 1 and Card Enable 2. These signals
enable even and odd numbered address bytes. CE1
enables even numbered address bytes and CE2
enables odd numbered address bytes.
INPACK Y01 D12 I Input acknowledge. This signal is asserted by the
PC Card when it can respond to an l/O read cycle
at the current address.
DMA Request. This pin may be used as the DMA
request signal during DMA operations from a 16-bit
PC Card that supports DMA. If used as a strobe,
the PC Card asserts this signal to indicate a
request for a DMA operation.
IORD L04 E17 O I/O read. IORD is asserted by the PCI1250A to
enable 16-bit t/O PC Card data output during host
l/O read cycles.
DMA Write. This pin is used as the DMA write
strobe during DMA operations from a 16-bit PC
Card which supports DMA. The PCI1250A asserts
this signal during DMA transfers from the PC
Card to host memory.