ZyXEL Communications 2864 Series, User Manual, Page: 207 / 267

18–1
Chapter 18
DIAGNOSTICS
The 2864 series modems provide several diagnostic capabilities:
• Power-on Self-Test
• Analog Loopback Test
• Analog Loopback with Self-Test
• Local Digital Loopback Test
• Remote Digital Loopback Test
• Remote Digital Loopback with Self-Test
• Line Condition Status Display
• Re-transmission Indicator
• Throughput Display
• Link Status Report
• Modem Reset
All these tests apply to the asynchronous or synchronous, error controlled or non-
error controlled, data compression enabled or disabled data mode. You can use these
capabilities to verify the line condition and the modem's functioning and perform-
ance, and to locate the source of a communication problem.
Power-on Self-test
At each power-up or upon a reset command from the panel, the modem will test the
ROM code checksum, system RAM memory, DSP code checksum, DSP RAM
memory, EEPROM, digital circuits, and the analog circuit calibrations.
On the LCD model, the LCD panel will display the results of the power-on self-test:
0 SYSTEM TESTING.... Self-test indicator. If no error occurs, this message
will last until the end of the test.
1 ROM TEST FAIL.... ROM code checksum error.
2 RAM TEST FAIL.... System RAM fails.