Multi-Purpose Pin Interface Functional Overview
Unified Memory Architecture Control
Copyright © 2002 Marvell
CONFIDENTIAL
Doc. No. MV-S300165-00, Rev. A
May 21, 2002, Preliminary
Document Classification: Proprietary Information
Page 77
8.6
Unified Memory Architecture Control
The GT-64260A can be configured to support Unified Memory Architecture (UMA) at the reset configuration (see
Section 20, "Reset", on page 144
Also, the GT-64260A can be configured to act as a UMA master or slave. UMA systems require two additional sig-
nals for arbitration of the SDRAM interface. For more information, see the GT-64260A datasheet’s "Unified Mem-
ory Architecture Support" section.
8.7
DMA End of Transfer
When the EOT support is enabled (the Channel Control register’s
EOTEn
bit [18] is set to ‘1’), the IDMA engine
transfer can be terminated by external hardware via EOT pins. For more information, see the GT-64260A
datasheet’s "End of Transfer" section.
8.8
Timer Counter Enable
When an external TCen support is enabled (the Timer/Counter Control register’s
TCxTrig
bit [2] is set to ‘1’), the
Timer/Counter can be stopped by external hardware via TCEn pins.
The MPP interface can be configured as a TCEn[7:0] input. Each timer/counter has its own Tcen input pin. For
more information on the Timer/Counter unit, see the GT-64260A datasheet’s "Timer/Counters" section.
Note
If using an external count enable input, it is necessary to configure the appropriate MPP pin prior to counter
activation.
8.9
Initialization Active
The MPP interface can be configured as InitAct output. It will be driven High during the serial ROM initialization.
For more information, see the GT-64260A datasheet’s "MPP Multiplexing" section.
Notes
•
When serial initialization is enabled, one of the MPP pins must be configured as InitAct.
•
Since the InitAct pin is configured as input at reset, it must be pulled up.
8.10 BRG Clock
The MPP interface can be configured as BRG input/output. One of the MPP pins can be configured to BclkIn, as
an input clock, to one of the BRGs and another MPP pin as BClkOut0, as an output clock of BRG0.