This chapter describes procedures for troubleshooting an installed CodeNet card. You can usually ascertain whether or not your card is functioning correctly by observing the activity of the diagnostic / activity LEDs located on the front panel of the card.

Table 1-1: Overview of Front Panel LEDs
830X	Color
COL	Yellow
RX / TX	Green
LL	Yellow
JAB	Yellow
HL	Yellow

COL: Collision Presence (All Cards) - This LED illuminates when a card is receiving a packet at the same time it is transmitting a packet. Occasional collisions are normal in an Ethernet network. This does not denote an error condition.
RX/TX: Receive Activity/Transmit Activity (All Cards) - This dual purpose LED illuminates when the card is receiving or sending a packet. This indicates normal operation.
LL: Link Fault (8300 & 8302) - This LED illuminates when the ffiber cable is broken, provided break protection is on.
LL: Low Light (8301) - This LED illuminates if the receiver power is less than the receiver intensity.
JAB: Jabber (All Cards) - This LED illuminates when a transceiver interlock circuit is activated. This circuit prevents a runaway AUI controller from saturating the network.
HL: High Light (8300 & 8302) - This LED illuminates if the received power is greater than the receiver saturation level.

1.2.1 Ffiber Broker/Jabber Indicators
Use the following table if your card is a CodeNet 8300 or 8302:

Condition Code	Jabber Auto Reset Switch	Link Fault LED	Jabber LED	Error Condition
1 2 3 4	On On Off Off	Steady Off Steady Off	Flashing Flashing Off Flashing	Ffiber Broken Jabbering Ffiber Broken Jabbering

Cond.	Correction
1 or 3	Check connection between cable and card. See following steps.
2 or 4	Indicates transmission taking too long. Doesn't harm network, just slows it down. Use checkout steps below.

In conditions (1) and (2), because the Jabber Auto-Reset switch is ON, the card will reset itself and continue operating normally without powering down. In conditions (3) and (4), you must power down the computer, correct the problem and power up again to reset it.

If the link fault LED is on, check to make sure that cables are connected properly and, if using SMA-906 connectors, that the half-length alignment sleeves are on the tips of the connectors going into the 8300 or 8302, and that full length alignment sleeves are present in the passive star ports. If the link fault LED remains on, test the optical power in the receive ffiber.

To test, you must first disconnect all other cables from the star or shut down all DTE's connected to the star. Put switch 5 in the down (test) position. If the average power at the receive ffiber is less than -40 dBm for an 8300, or less than -33 dBm for an 8302, the problem is is probably in the ffiber or the passive star. Check the loss in the passive star using a short jumper cable. If ffiber loss in the passive star using a short jumper cable. If ffiber loss is determined to be excessive, try cleaning the connector ends with a soft cloth or lens tissue dampened in isopropyl alcohol.

If ffiber and passive star light levels are deemed acceptable, test the output power of the 8300 or 8302 and compare to specifications.
Note: The power meter will read average power which is 3 dB less than the peak power specifications.

Caution: You must return switch 5 to the up position before reconnecting to the network.

1.2.2 CodeNet 8300 and 8302 "High Light" Indicator

On the 8300 and 8302 the "High Light" indicator (HL, if ON, indicates that the receiver is being saturated (receiving too much optical power). While this is not injurious to your network, it will most likely slow it down. This condition should be corrected by attenuating the incoming signal.

The front panel lights on the 8301 indicate the following conditions. If any of these indicators illuminate, follow the error correction steps given below or in section 1.4, which are applicable to all 3 units.

LOW LIGHT (LL) LED ON

If the Low Light LED is on after cables have been connected and the other adapter card or concentrator has been powered up, check to make sure that cables are connected properly and, if using SMA-906 connectors, that the half-length alignment sleeves are on the tips of the connectors going into the 8301. If the Low Light LED remains on, disconnect the RX ffiber from the adapter card and connect it to an optical power meter (CodeNet CTC-2000 or equivalent). If the average optical power meter is less than -30 dBm, there is excessive loss in the ffiber or the companion unit's transmitter is not supplying sufficient power. Try cleaning the fiber ends with a soft cloth or lint free paper dampened in alcohol and test the transmitter output of the companion unit.

If a power meter is not available, a simple pen light is an excellent optical source for checking ffiber continuity. Shine the light in one end of the cable. If you see the light on the other end, the ffiber is not broken. If you see no light, the ffiber is broken. Replace the cable.

If any of the CodeNet cards don't operate properly, follow the steps listed here to verify correct installation,

1. Verify that the network connectors are securely attached (TX to RX, RX to TX)

2. Check the cable connections to other computers and devices.

3. Ensure that the interconnecting cables used meet Codenoll standards.

4. Ensure that you have correctly configured your system for the CodeNet cards being used, employing the configuration file on the Installation diskette.

5. Ensure that you have copied any required software drivers from the Installation diskette as instructed in documentation included in your network software package.

6. If more than one 8300, 8301 or 8302 card is installed, ensure that you have selected a different IRQ channel for each.

7. Verify that the network software is loaded correctly.

8. Ensure that the CodeNet card is completely seated in the computer's expansion slot.

9. Verify all appropriate alignment sleeves (if any) are present.

10. Ensure connector and faces are free of dirt and debris. Clean with soft cloth or lint free paper dampened with isopropyl alcohol.