07-29-2006 05:44 PM
07-31-2006 11:26 AM
Hi Noah,
You should find on page 161 of the PCI specifications that information regarding required pull-ups for the control lines on a PCI board. I emailed this document to you earlier in the day, so you should find it without trouble.
Excerpt:
PCI control signals always require pull-up resistors (pulled up to Vcc of the signaling
environment) on the system board (not the add-in card) to ensure that they contain stable
values when no agent is actively driving the bus. This includes
FRAME#, TRDY#, IRDY#,DEVSEL#
, STOP#, SERR#, PERR#, LOCK#, INTA#, INTB#, INTC#, INTD#, REQ64#,and
ACK64#. The point-to-point and shared 32-bit signals do not require pull-ups; busparking ensures their stability. Refer to Section 3.8.1 for special requirements for
terminating
AD[63::32], C/BE[7::4]#, and PAR64. Refer to Section 4.3.7 for pull-up anddecoupling requirements for
PRSNT1# and PRSNT2#. Refer to Section 7.7.7 for pull-upand decoupling requirements for
M66EN.