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PortServer Terminal Server
Test 5 - Built-In UART External Loopback Test
Same as Test 4, but uses external loopback. From the front panel, press the right pushbutton (
) to select the port to test. The display will cycle from “01” to “16” or highest UART plus “All”.
With the port selected, press the left pushbutton ( ) to start the test.
In Test 5 (Async External Test), each port loops back on itself instead of looping back between
ports. This requires a test plug made from an RJ-45 connector at one end, with the pins wired as
follows:
Output Pins Input Pins
PIN 3 (RTS) to PIN 1 (RI) and PIN 8 (CTS)
PIN 5 (SOUT) to PIN 6 (SIN)
PIN 9 (DTR) to PIN 2 (DSR) and PIN 10 (DCD)
Test 6 - NIC/DMA Test
This tests the 8390 NIC's ability to transmit, receive, and verify data in three diagnostic modes.
To ensure that all test display information and test results are correct, the PortServer unit must be
disconnected from the Ethernet network, and the PortServer’s Ethernet connector properly termi-
nated.
Test 7 - Watchdog Timer Test
This test checks out the watchdog timer, a hardware feature used to ensure system reliability.
The firmware must access PCS 5 within 1.6 seconds or the CPU will reset and jump to the reset
vector (0FFFF0h).
It is up to the system to keep accessing PCS 5 to prevent it from resetting. This will force the
POST diagnostic sequence to begin. This test allows the timer to expire. Normal test execution
causes the user diagnostics to jump to the reset vector and begin the POST diagnostic sequence.
The test will fail after three seconds if the timer has not expired.
