82801E datasheet(77/84 Pages) INTEL

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Intel® 82801E C-ICH

Advance Information Datasheet

5.0

Testability

5.1

Test Mode Description

The 82801E C-ICH supports two types of test modes, a tri-state test mode and an XOR Chain test

mode. Driving RTCRST# low for a specific number of PCI clocks while PWROK is high activates

a particular test mode as described in Table 56.

Note:

RTCRST# can be driven low any time after PCIRST# is inactive.

Figure 29 illustrates the entry into a test mode. A particular test mode is entered upon the rising

edge of the RTCRST# after being asserted for a specific number of PCI clocks while PWROK is

active. To change test modes, the same sequence should be followed again. To restore the 82801E

C-ICH to normal operation, execute the sequence with RTCRST# being asserted so that no test

mode is selected as specified in Table 56.

Table 56. Test Mode Selection

Number of PCI Clocks RTCRST# Driven Low After

PWROK Active

Test Mode

No Test Mode Selected

XOR Chain 1

XOR Chain 2

XOR Chain 3

XOR Chain 4

All “Z”

9 - 24

Reserved. DO NOT ATTEMPT

>24

No Test Mode Selected

Figure 29. Test Mode Entry (XOR Chain Example)

RSMRST#

PWROK

RTCRST#

Other Signal

Outputs

N Number of PCI Clocks

Test Mode Entered

All Output Signals Tri-Stated

XOR Chain Output Enabled

82801E Datasheet(PDF) 77 Page - Intel Corporation