MPC821 datasheet(44/242 Pages) NXP

44 / 242 page

Functional Description

MPC8XXFADS Design Specification—Rev 0.1

PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE

4•10

PCMCIA PortA

To enhance PCMCIA i/f development, a dedicated PCMCIA port is provided on the FADS. Support

is given to 5V only PC-Cards, PCMCIA standard 2.1+ compliant. All the necessary control signals are

generated by the MPC itself. To protect MPC signals from external hazards, and to provide sufficient

drive capability, a set of buffers and latches is provided over PC-Card’s address, data & strobe lines.

To conform with the design spirit of the FADS, i.e., making as much as possible MPC resources avail-

able for external application development, input buffers are provided for input control signals, con-

trolled by the PCC_EN~ bit in BCSR1, so the PCMCIA port may be Disabled / Enabled at any time,

by writing ’1’ / ’0’ to that bit. When the PCMCIA channel is disabled, its associated pins are available

for off-board use via the expansion connectors.

A loudspeaker is provided on board and connected to SPKROUT line of the MPC. The speaker is

buffered from the MPC and low-pass filtered. When the PCC_EN~ bit in BCSR1 is negated (high) the

speaker buffer is tri-stated so the SPKROUT signal of the MPC may be used for alternate function.

Since it is not desirableB to apply control signals to unpowered PC-Card, the strobe / data signal

buffers / transceivers are tri-stated and may be driven only when the PC-Card is powered.

The block diagram of the PCMCIA port is shown in FIGURE 4-6 "PCMCIA Port Configuration" on

page 43.

A. As the MPC801 does not have a PCMCIA port, this port is not operational with an MPC801 daughter board.

B. This since the PC-Card might have protection diodes on its inputs, which will force down input signals re-

gardless of their driven level.

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

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