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29 September 1997 – Subject To Change
Hardware Interface
3–3
21164PC Signal Names and Functions
3.2 21164PC Signal Names and Functions
The 21164PC is contained in a 413-pin interstitial pin grid array (IPGA) package.
There are 264 functional signal pins, 2 spare signal pins (unused), 5 voltage refer-
ence pins (unused), 46 external power (Vdd) pins, 22 internal power (Vddi) pins,
and 74 ground (Vss) pins.
The following table defines the 21164PC signal types referred to in this section:
Signal Type
Definition
B
Bidirectional
I
Input only
O
Output only