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PEB383 User Manual
July 25, 2011
Integrated Device Technology, Inc.
Confidential - NDA Required
10.
Reset and Clocking
Topics discussed include the following:
•
•
10.1
Reset
The PEB383 inputs resets from upstream devices, and drives reset to downstream devices.
PCIE_PERSTn is the reset input to the bridge, and is normally connected to a power-on reset controller
at the system level. The PEB383 drives reset onto the PCI bus using PCI_RSTn (see
Table 25: Reset Summary
Reset
Level
PCI Definition
Trigger
EEPROM
Load
PEB383 Actions
0
Cold reset
Warm reset
PCIE_PERSTn
Yes
• Initialize all registers to known state (including
sticky)
• Drive and release PCI_RSTn 1 ms after
PCIE_PERSTn is released
1
Hot reset
Reset message or
DL_down state
Yes
• Initialize all registers to known state (except
sticky
• Drive and release PCI_RSTn 1 ms after
PEB383 is completed reset
2
PCI bus reset
Set reset bit in CSR
through configuration
cycle
No
• Hold PCI_RSTn low for 1 ms, or until bit is
cleared by software, which ever is longer
• Drain traffic
• Drop request TLPs
• Enumerate bus mode and clock speed (if clock
master)
• Do not initialize CSR