ADM-XRC SDK 2.8.1 User Guide (Linux)
© Copyright 2001-2009 Alpha Data
Model | Supported |
ADM-XRC | ![]() |
ADM-XRC-P | ![]() |
ADM-XRC-II-Lite | ![]() |
ADM-XRC-II | ![]() |
ADM-XPL | ![]() |
ADM-XP | ![]() |
ADP-WRC-II | ![]() |
ADP-DRC-II | ![]() |
ADP-XPI | ![]() |
ADM-XRC-4LX | ![]() |
ADM-XRC-4SX | ![]() |
ADM-XRC-4FX | ![]() |
ADPE-XRC-4FX | ![]() |
ADM-XRC-5LX | ![]() |
ADM-XRC-5T1 | ![]() |
ADM-XRC-5T2 | ![]() |
ADM-XRC-5T2-ADV | ![]() |
ADM-XRC-5TZ | ![]() |
ADM-XRC-5T-DA1 | ![]() |
The Clock utility serves two purposes:
clock [options ...] [clock input] [frequency]
Option | Argument type | Meaning |
-card | base 10 integer | ID of card to open |
-index | base 10 integer | Index of card to open |
-measure | Disables measurement of approximate frequency. | |
+measure | Enables measurement of approximate frequency (default) |
When run with no arguments, the Clock utility displays a list of clock inputs and their 1-based indices. For example, on an ADM-XRC-5T2 card, running Clock with no arguments produces the following output:
Clock pins available on specified card: Clock input Programmable Clock generator index 1 LCLK Yes 0 2 MCLKA Yes 1 3 MCLKB Yes 1 4 REFCLK No N/A 5 XRM_CLKIN No N/A 6 XRM_MGTREF No N/A 7 PCIE100A No N/A
This indicates that of the seven clock inputs, only LCLK (1), MCLKA (2) and MCLKB (3) are programmable. LCLK corresponds to clock generator 0, and MCLKA and MCLKB are copies of the output of clock generator 1.
To measure the frequency of a particular clock input, specify the index of the clock input as the first argument. For example, to measure the local bus clock frequency, run Clock as follows:
clock 1
This produces output in the following form (actual measured values may vary depending on what LCLK frequency has previously been programmed, if any):
Measuring frequency of clock input 1 (LCLK)... Initial counter value = 625869 Final counter value = 40624672, delta = 39998803
In this case, the 'delta' value indicates that the frequency of the local bus clock, LCLK, is approximately 40 MHz. Note that since the above command-line only measures the local bus clock frequency (without programming the clock generator), the measured frequency depends upon whatever the current local bus clock frequency happens to be.
The final mode in which Clock can be run both programs a clock generator and measures the resulting frequency. For example, to program the MCLKA/MCLKB clock generator on an ADM-XRC-5T2 card for a frequency of 250 MHz, the following command-line would suffice:
clock 2 250
and this produces output in the following form (actual measured values may vary slightly):
Programming clock generator 1 for 250.00 MHz... Actual programmed frequency = 250000000.00 Hz Measuring frequency of clock input 2 (MCLKA)... Initial counter value = 7709995 Final counter value = 257703771, delta = 249993776
Here, the 'delta' value indicates that the measured frequency of MCLKA is as expected, approximately 250 MHz.
This application uses the Clock sample FPGA design (VHDL).