Cirrus Logic EP93xx User Manual

Page 782

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DS785UM1

Copyright 2007 Cirrus Logic

IDE Interface
EP93xx User’s Guide

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Note: At most, one of the above 3 bits should be set to 1 at any time. If more than one is set, the

results will be unpredictable, and the data invalid.

MODE:

Speed mode number. (0 to 4 defined for PIO, 0 to 2
defined for MDMA, 0 to 4 defined for UDMA).

WST:

Wait State for Turn. Number of HCLK cycles to hold the
data bus after a PIO write operation.

IDEMDMAOp

Address:

0x800A_0008 Read/Write

Default:

0x0000_0000

Definition:

IDE MDMA Configuration Register.

Bit Descriptions:

RSVD:

Reserved. Unknown during read, ignored during write.

MEN:

Enable Multiword DMA operation.
1 - to start MDMA
0 - to terminate MDMA by the host.

RWOP:

Read or write operation selection:
0 - Read
1 - Write.

IDEUDMAOp

Address:

0x800A_000C - Read/Write

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RSVD

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RSVD

RWOP

MEN

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RSVD

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RSVD

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UEN

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