
RELEASED
DATA SHEET
PM7382 FREEDM-32P256
ISSUE 3
PMC-2010333
FRAME ENGINE AND DATA LINK MANAGER 32P256
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA,INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
26
Pin Name Type
Pin
No.
Function
STOPB
I/O
R4
The active low stop signal (STOPB) requests the
initiator to stop the current bus transaction.
When STOPB is set high by a target, the initiator
continues with the transaction. When STOPB is
set low, the initiator will stop the current
transaction.
When the FREEDM-32P256 is the initiator,
STOPB is an input. When STOPB is sampled
low, the FREEDM-32P256 will terminate the
current transaction in the next PCICLK cycle.
When the FREEDM-32P256 is the target,
STOPB is an output. The FREEDM-32P256 only
issues transaction stop requests when
responding to reads and writes to configuration
space (disconnecting after 1 DWORD
transferred) or if an initiator introduces wait
states during a transaction.
When the FREEDM-32P256 is not involved in
the current transaction, STOPB is tristated.
STOPB is updated on the rising edge of PCICLK
or sampled on the rising edge of PCICLK
depending on whether it is an output or an input.
IDSEL
Input
L1
The initialization device select signal (IDSEL)
enables read and write access to the PCI
configuration registers. When IDSEL is set high
during the address phase of a transaction and
the C/BEB[3:0] code indicates a register read or
write, the FREEDM-32P256 performs a PCI
configuration register transaction and asserts
the DEVSELB signal in the next PCICLK period.
IDSEL is sampled on the rising edge of PCICLK.