634 Chapter14
Analyzer Messages
Interpreting Analyzer Messages
The 10-Digit Failure Code
The 10-digit segment provides further failure information for the I/O
address bus, the I/O data bus, and the A16 video RAM circuitry. Each
digit of the 10-digit hexadecimal segment must be translated to its
binary equivalent to obtain the failure information.
The 10-digit failure code section is divided into three separate codes.
The 10-digit failure code example (0625C1F72D) is separated into three
codes as shown below.
FAIL: DF40 (06) (25C1) (F72D)
Each failure code from the example is converted from hexadecimal to
binary and interpreted in Table 14-4, Table 14-5, and Table 14-6.
The I/O Address Bus Failure Code.
The first two digits of the 10-digit code identify the failed address lines
on the I/O address bus. Convert the two digits to binary and interpret
them with Table 14-4.
Table 14-4 I/O Bus Address Failure-Code Interpretation
Digits From
Example
Equivalent
Binary Value
A16 Circuit Tested A16 Reference
Designator
8 Not Used
4 Not Used
2 Not Used
0→ 1 Error at ADR 4 U18
8 Error at ADR 3 U18
6→ 4 Error at ADR 2 U18
→ 2 Error at ADR 1 U18
1 Error at ADR 0 U18