
Table of Contents
(Continued)
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10
Revision1.2
P
4.0
LPC Bus Interface
4.1
OVERVIEW ...............................................................................................................................90
4.2
LPC TRANSACTIONS ...............................................................................................................90
4.3
CLKRUN FUNCTIONALITY ......................................................................................................91
4.4
INTERRUPT SERIALIZER ........................................................................................................91
5.0
X-Bus Extension
5.1
OVERVIEW ...............................................................................................................................92
5.2
X-BUS TRANSACTIONS ...........................................................................................................92
5.2.1
Transaction Clock ........................................................................................................93
5.2.2
Programmable Range Chip Select ..............................................................................93
5.2.3
LPC and FWH Address-to-X-Bus Address Translation ...............................................93
5.2.4
Indirect Memory Read and Write Transactions ...........................................................95
5.2.5
Mode 0, Normal Address X-Bus Transactions ............................................................95
5.2.6
Mode 0, Normal Address, Fast X-Bus Transactions ...................................................97
5.2.7
Mode 0, Normal Address, Turbo X-Bus Transactions .................................................99
5.2.8
Mode 1, Normal Address Transactions .....................................................................100
5.2.9
Latched Address Mode X-Bus Transactions .............................................................101
5.3
X-BUS PROTECTION .............................................................................................................105
5.4
X-BUS REGISTERS ................................................................................................................107
5.4.1
X-Bus Register Map ..................................................................................................107
5.4.2
X-Bus Configuration Register (XBCNF) ....................................................................108
5.4.3
X-Bus Select Configuration Registers (XZCNF0 to XZCNF3) ...................................108
5.4.4
X-Bus IRQ Configuration Register (XIRQC) ..............................................................110
5.4.5
X-Bus Indirect Memory Address Register 0 (XIMA0) ................................................111
5.4.6
X-Bus Indirect Memory Address Register 1 (XIMA1) ................................................111
5.4.7
X-Bus Indirect Memory Address Register 2 (XIMA2) ................................................112
5.4.8
X-Bus Indirect Memory Address Register 3 (XIMA3) ................................................112
5.4.9
X-Bus Indirect Memory Data Register (XIMD) ...........................................................112
5.4.10
X-Bus Select Mode Register (XZM0 to XZM3) ..........................................................113
5.4.11
Host Access Protect Register (HAP0 to HAP1) .........................................................114
5.5
USAGE HINTS ........................................................................................................................115
5.6
X-BUS EXTENSION REGISTER BITMAP .............................................................................116
6.0
ACCESS.bus Interface
6.1
OVERVIEW .............................................................................................................................117
6.2
FUNCTIONAL DESCRIPTION ................................................................................................117
6.2.1
Bus Signals ................................................................................................................117
6.2.2
Data Transactions .....................................................................................................117
6.2.3
Start and Stop Conditions ..........................................................................................118
6.2.4
Acknowledge (ACK) Cycle ........................................................................................118
6.2.5
Acknowledge after Every Byte Rule ..........................................................................119
6.2.6
Addressing Transfer Formats ....................................................................................119