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Chapter 2. Signal Descriptions and Clocking
2-7
Detailed Signal Descriptions
During reset, the MPC8240 ignores most input signals (except for PCI_SYNC_IN and the
reset configuration signals), and drives most of the output signals to an inactive state.
Table 2-2 shows the states of the output-only signals that are not used as reset configuration
signals during system reset.
2.2 Detailed Signal Descriptions
The following subsections describe the MPC8240 input and output signals, the meaning of
their different states, and relative timing information for assertion and negation. In cases
where signals serve multiple functions (and have multiple names), they are described
individually for each function.
2.2.1 PCI Interface Signals
This section provides descriptions of the PCI interface signals on the MPC8240. Note that
throughout this manual, signals and bits of the PCI interface are referenced in little-endian
format. For more information on the operation of the MPC8240 PCI interface, see
Chapter 7, “PCI Bus Interface.” Refer to the PCI Local Bus Specification, Revision 2.1 for
a thorough description of the PCI local bus and specific signal-to-signal timing
relationships for the PCI bus.
Table 2-2. Output Signal States During System Reset
Interface
Signal
State During System Reset
PCI
GNT[3:0]
INTA
High impedance
Memory
CAS/DQM[0:7]
Driven high
RAS/CS[0:7]
RCS1
SDRAS
SDCAS
WE
Negated
PAR[0:7]/AR[19:12],
SDMA[11:0]
SDMA12/SDBA1
SDBA0
High impedance
Clock
PCI_CLK[0:4]
PCI_SYNC_OUT
SDRAM_CLK[0:3]
SDRAM_SYNC_OUT
CKO
Driven
System control
TRIG_OUT
High impedance
Debug
DA[15:11], DA2
Driven high
Test/Configuration
TDO
Negated
Содержание MPC8240
Страница 1: ...MPC8240UM D Rev 1 1 2001 MPC8240 Integrated Processor User s Manual ...
Страница 38: ...xviii MPC8240 Integrated Processor User s Manual TABLES Table Number Title Page Number ...
Страница 48: ...xlviii MPC8240 Integrated Processor User s Manual Acronyms and Abbreviations ...
Страница 312: ...6 94 MPC8240 Integrated Processor User s Manual ROM Flash Interface Operation ...
Страница 348: ...7 36 MPC8240 Integrated Processor User s Manual PCI Host and Agent Modes ...
Страница 372: ...8 24 MPC8240 Integrated Processor User s Manual DMA Register Descriptions ...
Страница 394: ...9 22 MPC8240 Integrated Processor User s Manual I2O Interface ...
Страница 412: ...10 18 MPC8240 Integrated Processor User s Manual Programming Guidelines ...
Страница 454: ...12 14 MPC8240 Integrated Processor User s Manual Internal Arbitration ...
Страница 466: ...13 12 MPC8240 Integrated Processor User s Manual Exception Latencies ...
Страница 516: ...16 14 Watchpoint Trigger Applications ...
Страница 538: ...B 16 MPC8240 Integrated Processor User s Manual Setting the Endian Mode of Operation ...
Страница 546: ...C 8 MPC8240 Integrated Processor User s Manual ...
Страница 640: ...INDEX Index 16 MPC8240 Integrated Processor User s Manual ...