Product manual

Preliminary CompactFlash Memory Card Product Manual

4.7 True IDE Mode I/O Transfer Function

4.7.1 True IDE Mode I/O Function

The CompactFlash Memory Card can be

configured in a True IDE Mode of operation. This

CompactFlash Card is configured in this mode

only when the -OE input signal is grounded by the

host. In this True IDE Mode, the PCMCIA protocol

and configuration are disabled and only I/O

operations to the Task File and Data Register are

allowed. In this mode, no Memory or Attribute

Registers are accessible to the host. CompactFlash

Cards permit 8 bit data accesses if the user issues a

Set Feature Command to put the device in 8 bit

Mode.

Note: Removing and reinserting the CompactFlash

Memory Card while the host computer’s power is on

will reconfigure the CompactFlash Card to PC Card

ATA mode from the original True IDE Mode. To

configure the CompactFlash Card in True IDE

Mode, the 50-pin socket must be power cycled with

the CompactFlash Card inserted and -OE (output

enable) grounded by the host.

The following table defines the function of the

operations for the True IDE Mode.

Table 4-17 IDE Mode I/O Function

Function Code -CE2 -CE1 A0 -IORD -IOWR D15-D8 D7-D0

Invalid Mode

L L X X X High Z High Z

Standby Mode

H H X X X High Z High Z

Task File Write

H L 1-7h H L Don't Care Data In

Task File Read

H L 1-7h L H High Z Data Out

Data Register Write

H L 0 H L Odd-Byte

Even-Byte

Data Register Read

H L 0 L H Odd-Byte

Out

Even-Byte

Out

Control Register Write

L H 6h H L Don't Care Control In

Alt Status Read

L H 6h L H High Z Status Out