PEX 8632-AA Quick Start Hardware Design Guide, Version 1.1
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© 2007 PLX Technology, Inc. All Rights Reserved.
Table 7. STRAP_RESERVED Ball External Pull-Up/Pull-Down Resistor Requirements –
12-Port Mode
Ball/Signal Name
Pull-Up/Pull-Down
STRAP_RESERVED0
Must be tied Low
STRAP_RESERVED1
Must be pulled High
STRAP_RESERVED2
Must be tied Low
STRAP_RESERVED16
Must be tied directly to Ground (VSS)
STRAP_RESERVED17#
Must be tied High
1.8
GPIO Balls
1.8.1
GPIO Balls – 8-Port Mode
The PEX 8632 has 20 GPIO balls – 12 are dedicated GPIO balls, and eight share GPIO and
PEX_PORT_GOOD[7:0]# functions in standard operation. Depending upon the settings of the Test mode
balls, STRAP_TESTMODE[3:0], the GPIO balls can be set as input, output, and/or bidirectional. Eight of
the 12 dedicated GPIO balls, GPIO[7:0], can also be configured as PERST# outputs for the SHPC, when
the PEX 8632 is reset.
1.8.2
GPIO Balls – 12-Port Mode
The PEX 8632 has 20 GPIO balls – eight are dedicated GPIO balls, and 12 share GPIO and
PEX_PORT_GOOD[11:0]# functions in standard operation. Depending upon the settings of the Test
mode balls, STRAP_TESTMODE[3:0], the GPIO balls can be set as input, output, and/or bidirectional.
The eight dedicated GPIO balls can also be configured as PERST# outputs for the SHPC, when the PEX
8632 is reset.
