Arbiter (arbiter), Pull up (pull_up) – Altera PCI Compiler User Manual
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User Guide Version 11.1
Altera Corporation
PCI Compiler
October 2011
Testbench Specifications
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Target retry
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Target abort
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Target terminated with disconnect-A (target terminated with data)
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Target terminated with disconnect-B (target terminated without
data)
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Master abort
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Target not responding
The bus monitor reports the target termination messages depending on
the state of the trdyn, devseln, and stopn signals during a transaction.
The bus monitor reports a master abort if devseln is not asserted within
four clock cycles from the start of a PCI transaction. It reports that the
target is not responding if trdyn is not asserted within 16 clock cycles
from the start of the PCI transaction. You can modify the bus monitor to
include additional PCI protocol checks as needed by your application.
Arbiter (arbiter)
This module simulates the PCI bus arbiter. The module is a two-port
arbiter in which the device connected to port 0 of the arbiter has a higher
priority than the device connected to port 1. For example, if device 0
requests the PCI bus while device 1 is performing a PCI transaction, the
arbiter removes the grant from device 1 and gives it to device 0. This
module allows you to simulate bus parking on devices connected to
port 0 by setting the Park parameter to true. You change the value of this
parameter in the Altera PCI testbench top-level file.
Pull Up (pull_up)
This module simulates the pull up functionality on the PCI signals. The
ad
, cben, framen, irdyn, trdyn, stopn, devseln, perrn, and serrn
signals of the PCI bus are pulled with a weak high value. This action is
necessary to ensure that these signals are never floating or unknown
during simulation.