Intel® Stratix® 10 GX Transceiver Signal Integrity Development Kit User Guide

ID 683206
Date 2/21/2023
Public
Document Table of Contents

6.3.13. Clock Controller

The Clock Controller application sets the Si570 programmable oscillators to any frequency between 10 MHz and 945 MHz and select frequencies to 1400 MHz. The oscillator drives a 2-to-6 buffer that drives a copy of the clock to all transceiver blocks of the FPGA.

The Clock Control applications runs as a stand-alone application. ClockControl.exe resides in the <package dir>\examples\board_test_system directory.

The Clock Control communicates with the MAX® V device on the board throught the JTAG bus. The Si570 programmable oscillator is connected to the MAX® V device through a 2-wire serial bus.

Figure 37. Clock Controller

The following sections describe the Clock Control controls

Serial Port Registers

The Serial Port Registers control shows the current values from the Si570 registers.
Note: For more information about the Si570 registers, refer to the Si570/Si571 data sheet available on the Silicon Labs website (www.silabs.com).

fXTAL

The fXTAL control shows the calculated internal fixed-frequency crystal, based on the serial port register values.
Note: For more information about the fXTAL value and how it is calculated, refer to the Si570/Si571 data sheet available on the Silicon Labs website (www.silabs.com)

Target Frequency

The Target frequency control allows you to specify the frequency of the clock. Legal values are between 10 MHz and 945 MHz and select frequencies to 1400 MHz. For example, 421.31259873 is possible within 100 parts per million (ppm). The Target Frequency control works in conjunction with the Set New Frequency Control.

Reset Si570

The clear control sets the Si570 programmable oscillator to the default frequency as follows:
  • Y3 = 644.53125 MHz
  • Y4 = 706.25 MHz
  • Y5 = 625 MHz
  • Y6 = 875 MHz

Set New Frequency

The Set New Frequency control sets the Si570 programmable oscillator frequency to the value in the Target frequency control. Frequency changes might take several milliseconds to take effect. You might see glitches on the clock during this time.
Note: Intel recommends resetting the FPGA logic after changing frequencies