Agilent Technologies FS2100 Manuale Utente

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The Latching Buffers 
The latching buffers are used only for state mode.  The entire 
PCI bus (except the clock) is latched in these buffers on the 
rising edge of the PCI clock.  The input to the latching buffers is 
output port 1 from the input buffers.  The latching buffers are IDT 
162511 latching buffers with party generation.  These buffers are 
tri-stated in timing mode.  In state mode their outputs go directly 
to the logic analyzer input terminators.
   
The User pin signals are not latched.
 
 
The input to the logic analyzer consists of 3 parts. 
The interface to the 
Logic Analyzer 
1.  The RC terminators (90 ohm/10pf) 
2.  The 40 pin headers 
3.  The 40 pin cables  
The user is instructed to remove the probe tip assemblies from 
the logic analyzer headers.  The 40 pin logic analyzer headers 
then go directly the 40 pin headers of the Analysis Probe 
provided cables.  Any unused cables can be removed from the 
Analysis Probe. 
The logic analyzer provides the power to the onboard logic.  No 
power is obtained from the target. 
 
The master clock is controlled by the front panel switches and is 
generated by the on-board CPLD devices.  When the user has 
loaded the DEMULTIPLEXED configuration file an additional 
Slave clock is added.  This Slave clock is the falling edge of the 
Analysis Probe generated AVALID signal.  This signal asserts 
with the first assertion of FRAME# and the rising edge of the PCI 
clock.  All of the PCI cycle bits are generated based on the 
latched version of the PCI control signals.  Their meaning is 
listed in the following table. 
The Clocking and Cycle 
bit Generation Logic 
 
Cycle bit name 
Function 
EOFT_L - End of Transaction 
True for one clock cycle and indicates 
the last cycle of a transaction 
CPERR_L - Calculated Parity 
Error 
True for one clock cycle and indicates 
that the on board parity logic has 
detected a parity that is different than 
the parity transmitted on the bus.  
Please note that the Parity Checking 
switch must be in the ON position. 
MABORT_L - Master Abort 
True when a Master Abort condition has 
been detected.  Five clock cycles on a 
single data transfer with no DEVSEL 
assertion and six clock cycles on a 
multi-beat transfer with no DEVSEL 
asserted.  Remains true for one clock 
cycle. 
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