| TSP Lab
| Sga-47 interface cards
| SGA-47
|
Hardware components - Sga-47 interface cards
The Sga47 card with ISA bus
The Sga-47 link interface cards have two LEDs on their rear panel.
State of these LEDs indicates the status of the PCM trunk connected.
Right after the PC power up, the leds are uninitialized, they are in
random state and their color has no meaning. After the Monitor program
has initialized the cards, the meanings of LEDs are the followings:
- no light - there is no PCM signal on the cable at all
- red - PCM signal is OK on direction 0, but no PCM on direction 1
- green - PCM signal is OK on direction 1, but no PCM on direction 0
- amber - PCM signal is OK on both directions
The state of the LEDs has a strong correlationship with the signs on the
display of the Monitor. When the monitor program starts up, all the
links have a '*****' sign on both direction. It means, that the cards
haven't reported the state of the link yet, or there was no signal on
that link since the Monitor started.
When the cards recognise a PCM signal, they tell it to the Monitor, and
an 'PCM_OK' sign is diplayed for the link. Then, if the signal breaks for
some reason (eg. the cable is disconnected), an 'NFRA' sign is
displayed. If the signal comes back (eg. the cable is connected again),
the 'PCM_OK' will come back too.
The Sga47P16 card with PCI bus
This type of interface card has four green LEDs on its backlane.
Although function of these LEDs similar to ones described above, the meaning is different,
because all LEDs sign the state of the directions separately. The nearest LED to connectors
signs state for direction 0 of channel 0 (lower connector). The second LED signs
state for direction 1 of channel 0. The other two LEDs show the state of directions
for channel 1 (upper connector).
Right after the PC power up, the LEDs are uninitialized, they are in
random state and their color has no meaning. After the Monitor program
has initialized the cards, the meanings of LEDs are the followings:
- no light - there is no PCM signal on the cable at all
- green - PCM signal is OK on that direction
Information shown in the Monitor software is same as with the Sga47 cards.