Emerson PMPPC7448 Manuale Utente

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System Controller:
 PCI Bus Control Signals
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PRESENT*:
PRESENT When grounded, this input signal indicates to a carrier that a PPMC module is 
installed.
RESET_OUT*:
RESET OUTPUT This output signal may be used to support a reset button or other reset 
source on the PPMC module. It is an open drain output from the PPMC module that 
becomes an input to the reset logic on the carrier card. To avoid reset loops, do not use 
RST* to generate RESET_OUT*.
REQ64*:
REQUEST 64-bit TRANSFER When asserted by the current bus master, this sustained 
three-state line indicates the ability to transfer data using 64 bits.
REQ*:
REQUEST This three-state signal indicates to the arbiter that a particular master wants to 
use the bus.
RST*:
RESET The assertion of this input signal brings PCI registers, sequencers, and signals to a 
consistent state. The carrier card generates this system reset signal (pull-up resistor 
required) as an input to all PPMC modules.
SERR*:
SYSTEMS ERROR This open-drain output signal is used to report any system error with 
catastrophic results.
STOP*:
STOP  A sustained three-state signal used by the current target to request that the bus 
master stop the current transaction.
TCK:
TEST CLOCK This input signal clocks state information and test data into and out of the 
device during operation of the TAP.
TDI:
TEST DATA INPUT This input signal serially shifts test data and test instructions into the 
device during TAP operations.
TDO:
TEST DATA OUTPUT This output signal serially shifts test data and test instructions out of 
the device during TAP operation.
TMS:
TEST MODE SELECT This input signal controls the state of the TAP controller in the device.
TRDY*:
TARGET READY A sustained three-state signal that indicates the target’s ability to com-
plete the current data phase of the transaction.
TRST*:
TEST RESET This input signal provides asynchronous initialization of the TAP controller.