PD6710/
’
22
—
ISA-to-PC-Card (PCMCIA) Controllers
50
Datasheet
Bits 1:0
—
V
PP
1 Power
These bits are intended to be used to control the power to the V
PP
1 pin of the PC Card.
Bit 4
—
V
CC
Power
Depending on the value of bit 5 below, setting this bit to
‘
1
’
will cause power to be applied to the
card. The V
CC
3.3V bit (see bit 1,
“
Misc Control 1
”
on page 70
) determines whether 3.3V or 5V
power is applied.
Bit 5
—
Auto-Power
When this bit is set to
‘
1
’
, the PD67XX causes power to the card to be turned on and off
automatically with the insertion and removal of a PC card from the socket.
Bit 7
—
Card Enable
When this bit is
‘
1
’
, the outputs to the PC Card are enabled if a card is present and card power is
being supplied. The pins affected include: -CE2, -CE1, -IORD, -IOWR, -OE, -REG, RESET,
A[25:0], D[15:0], and -WE (see
Table 2
).
V
PP
1 Power
Bit 1
Bit 0
VPP_PGM
VPP_VCC
PC Card Intended Socket Function
0
0
Inactive low
Inactive low
Zero volts to PC Card socket V
PP
1 pin
0
1
Inactive low
Active high
1
Selected card V
CC
to PC Card socket V
PP
1
pin
1
0
Active high
a
Inactive low
+12V to PC Card socket V
PP
1 pin
1
1
Inactive low
Inactive low
Zero volts to PC Card socket V
PP
1 pin
1. Under conditions where V
PP
1 power is activated. See
“
Power Control
”
on page 48
.
0
Power is not applied to the card: the -VCC_3 and -VCC_5 socket power control pins are
inactive high.
1
Power is applied to the card: if bit 5 is
‘
0
’
, or bit 5 is
‘
1
’
and -CD2 and -CD1 are active low,
then the selected -VCC_3 or -VCC_5 socket power control pin is active low.
0
V
and V
1 power control signals are activated independent of the socket
’
s -CD2 and -
CD1 input levels.
1
V
and V
1 power control signals are only activated if the socket
’
s -CD2 and -CD1 inputs
are active low.
0
Outputs to card socket are not enabled and are floating.
1
Outputs to card socket are enabled if -CD1 and -CD2 are active low and bit 4 is
‘
1
’
.