82801BA Datasheet, PDF (51/498 Pages) Intel Corporation – Intel 82801BA I/O Controller Hub 2 (ICH2) and Intel 82801BAM I/O Controller Hub 2 Mobile

Signal Description
2.20.2 Test Signals
2.20.2.1
Test Mode Selection
When PWROK is active (high), driving RTCRST# low for a number of PCI clocks (33 MHz) will
activate a particular test mode as specified in Table 2-21.
Note: RTCRST# may be driven low any time after PCIRST is inactive. Refer to Chapter 17, “Testability”
for a detailed description of the ICH2 test modes.
Table 2-21. Test Mode Selection
Number of PCI Clocks RTCRST#
driven low after PWROK active
<4
4
5
6
7
8
9–24
>24
Test Mode
No Test Mode Selected
XOR Chain 1
XOR Chain 2
XOR Chain 3
XOR Chain 4
All “Z”
Reserved. DO NOT ATTEMPT
No Test Mode Selected
2.20.2.2 Test Straps (82801BA ICH2 only)
The ICH2’s TP[0] (Test Point) signal must be pulled to VccSus3_3 with an external pull-up
resistor.
82801BA ICH2 and 82801BAM ICH2-M Datasheet
2-15