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© 2009 Advanced Micro Devices, Inc.
45732 AMD 780E Databook 3.10
Proprietary
7-1
Chapter 7
Testability
7.1
Test Capability Features
The RS780E has integrated test modes and capabilities. These test features cover both the ASIC and board level testing.
The ASIC tests provide a very high fault coverage and low DPM (Defect Per Million) ratio of the part. The board level
tests modes can be used for motherboard manufacturing and debug purposes. The following are the test modes of the
RS780E:
•
Full scan implementation on the digital core logic that provides about 99% fault coverage through ATPG (Automatic
Test Pattern Generation Vectors).
•
Dedicated test logic for the on-chip custom memory macros to provide complete coverage on these modules.
•
Improved access to the analog modules and PLLs in the RS780E to allow full evaluation and characterization of these
modules.
•
A JTAG test mode (which is not entirely compliant to the IEEE 1149.1 standard) to allow board level testing of
neighboring devices.
•
An XOR TREE test mode on all the digital I/O’s to allow for proper soldering verification at the board level.
•
A VOH/VOL test mode on all digital I/O’s to allow for proper verification of output high and output low voltages at
the board level.
These test modes can be accessed through the settings on the instruction register of the JTAG circuitry.
7.2
Test Interface
7.3
XOR Test
7.3.1
Description of a Generic XOR Tree
An example of a generic XOR tree is shown in the
Figure 7-1
.
Table 7-1
Pins on the Test Interface
Pin Name
Ball number
Type
Description
TESTMODE
D13
I
IEEE 1149.1 test port reset
DDC_DATA0/AUX0N
B8
I
TMS: Test Mode Select (IEEE 1149.1 test mode select)
I2C_DATA
A9
I
TDI: Test Mode Data In (IEEE 1149.1 data in)
I2C_CLK
B9
I
TCLK: Test Mode Clock (IEEE 1149.1 clock)
TMDS_HPD
D9
O
TDO: Test Mode Data Out (IEEE 1149.1 data out)
POWERGOOD
A10
I
I/O Reset