Simplex G-Link Receiver Card Data Sheet
Description
This Data Sheet describes a Simplex Destination card which
uses the HP G-Link HDMP-1024 receiver and optical or electrical physical
media. This card is equipped with an S-LINK interface and data can
be read with any S-Link read-out system.
Data Transfer Rate
The maximum clock rate (LCLK) is 40 Mhz. Minimum frequency of LCLK is 17.5
Mhz in 16 bit G-Link mode and 29.2 Mhz in 20 bit G-Link mode. 32 words
at 40 Mwords/sec (40Mhz LCLK) is above the specified data rate for G-Link
so not guaranteed but is inside the typical maximum data rate. Maximum
guaranteed data rate is 37.5 Mword/sec in 32 bit mode.
Since it is a simplex link, flow control is not available. The Uxoff#
input is reserved.
Operation modes
The "TP2" 20 bit mode selector jumper must be on the card when the transmitter
is in 20 bit mode.
| TP2 Jumper |
Min/Max/Typ. max
LCLK Mhz |
G-LINK
DIV1, DIV0 |
Serial Baud Rate at 40Mhz LCLK |
Error
detection |
| ON |
29.5/40/40 |
0,0 |
960 Mbaud |
Coding + Flag + Parity |
| OFF |
17.5/40/40 |
0,1 |
640 Mbaud |
Coding + Flag |
Table 1: S-LINK operation modes
4 jumpers can be used to select different operation modes. Flag mode
and 20 bit G-Link mode selection must be the same on both source and destination
cards.
| Jumpers TP[1..4] |
On |
Off |
| TP1 |
Flag bit mode: Flag bit can be used as an extra dataword. |
Flag bit is is internally alternated by G-Link for enhanced error detection. |
| TP2 |
20 bit G-Link mode |
16 bit G-Link mode |
| TP3 |
Link Synchronisation with on-board reference oscillator |
Link Synchronisation with sync. pulses (Fill Frames) |
| TP4 |
Reserved |
|
Table 2: Operation Modes
Optical Power and Board Temperature
Measurement
It is possible to measure received optical power and the temperature of
the circuit board next to the G-Link deserialiser (HDMP-1024). On a high-low
transition of the UTDO# (S-LINK) input a control word is sent whith optical
power and temperature measurement results. Optical power in dBm is -0.1
times the decimal value on bits 23-16. E.g. the binary "01000001" value
means -6.5dBm. Temperature can be read on bits 15-6 with 0.25 degrees accuracy
E.g. "0011000110" means 49.5 °C. UTDO must be pulled high
to receive G-Link data.
| LD [31..24] |
LD[23..16] |
LD[15..8] |
LD[7..6] |
LD5 |
LD[4..0] |
| Reserved |
-10*Power [dbm] |
Temperature [°C] |
Temperature [1/4°C] |
Alarm: Temp.>50°C |
"01100" |
Data output
The 16 MSB of the S-LINK data output are used for error checking
and diagnostic purposes. Table 4 shows the allocation of LD[31..0] bits.
The "#" symbol means an active low signal.
| LD31 |
LD30 |
LD29 |
LD28 |
LD[27..24] |
| CAV# (Control Word) |
DAV# (Data Word) |
ERR (G-Link error) |
FLAG (G-Link Flag) |
Free running counter |
| LD23 |
LD[22..20] |
LD[19..16] |
LD[15..0] |
| LINKRDY# |
Reserved |
Rx Data (Parity) |
Rx Data |
Table 3: Output Data bits
Error Detection
Word by word error reporting is possible using the "Error" signal of
G-Link.
Led Indicators
-
Power Led (green): It turns on when the card is powered with 5 V.
-
Link Up Led (green): This led turns on after the PLL of the G-Link
deserialiser is synchronised.
-
Data Error led (red): This Led turns on when G-Link Error.
It turns off on the high to low transition of URESET# input.
Selftest Led (red): This led is illuminated when UTD0# is low.
When UTDO# is pulled low, the optical power of the received light and the
temperature on board next to the serialiser is sent to the user in a control
word.
Last Updated on 30.06.1999 by Zoltán
Meggyesi