Siemens SIMATIC TIWAY 1 - Manual (Page 172)

ERROR CODES AND DIAGNOSTICS
UNILINK HOST ADAPTER 6–9
USER MANUAL
6.4 DIAGNOSTIC TESTS
The UNILINK Host Adapter provides both selectable and continuous
diagnostic tests to insure proper operation. The pattern shown on the six LEDs,
shown in Figure 6–1, will indicate whether the adapter is operating normally or
if an error has occurred.
LEDs Reset Number 2 Number 1
Figure 6–1 Adapter LEDs
The diagnostic tests verify the operation of the following.
D The integrity of the diagnostics Read Only Memory (ROM).
D The integrity of the adapter’s microprocessor, including its Random
Access Memory (RAM) and communications circuits.
D The integrity of the adapter’s Local Line and Host media boards, power
supply, and watchdog timer.
D The integrity of the Personality Interface Module (PIM) ROM.