Intel 41210 User Manual

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Intel
®
 41210 Serial to Parallel PCI Bridge Developer’s Manual
Signal Description
2.7
Reset Straps
The following signals are used for static configuration. These signals are all sampled on the rising 
edge of PERST#.
Table 7. 
Reset Strap Pins
Signal
I/O
Description
A_133EN
B_133EN
I
PCI-X 133 MHz Enable: The 133EN pin, when high, allows the PCI-X segment to run at 133 MHz 
when X_PCIXCAP is sampled high. When 133EN is low, the PCI-X segment runs only at 100 MHz 
when X_PCIXCAP is sampled high.
To tie high: Use an approximately 8.2 K
Ω
 resistor to pull to VCC33.
To tie low: Pull down to ground.
A_STRAP[6:0]
B_STRAP[6:0]
I
Internal Test Modes: For normal operation, X_STRAP[6] and [2:0] must be pulled low and 
X_STRAP[5:3] must be pulled high, as shown in the table below.
To tie high: Use approximately an 8.2 K
Ω
 resistor to pull up to VCC33.
To tie low: Pull down to VSS.
A_TEST[2:1]
B_TEST{2:1]
I
Internal Test Modes: These straps must be pulled high to VCC33. Use an approximately 8.2 K
Ω
 
resistor to pull up to VCC33.
CFGRETRY
I
Configuration Retry: This pin, when sampled high, sets the Configuration Cycle Retry Bit (bit 3) in 
the Bridge Initialization Register (
). 
When no local initialization is needed, this pin must be pulled low to VSS.
 for additional details.
Total
19
X_STRAP
Logic Level
0
0
1
0
2
0
3
1
4
1
5
1
6
0