HOLT ADK-2130mPCIe, Техническое руководство

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Holt Integrated Circuits
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J-TAG & FPGA Boot
The boot SPI flash memory is programmed at the factory but can be reprogrammed by the user with a
DIGILENT JTAG-HS2 USB programming cable (not provided) using the Xilinx Vivado tool.
When the FPGA successfully boots from the preprogrammed SPI Flash, D2 LED will light up. To reboot
the FPGA configuration sequence after reprogramming, press SW1 button. For normal operation this
switch can be ignored.
The FPGA uses three signals: M0, M1 and M2 inputs for configuration options. M0 and M1 are hard
wired so only M2 can be changed on this design. But default, a pull-down resistor keeps M2 low which
configures the FPGA to boot from the SPI Flash. For reprogramming, J2 pin 8 (see Figure 3 – Board
References) should be pulled high which will drive M2 high. For normal use, these connections don’t
need to be altered by the user, only if the user wants to customize the Verilog design and wants to
reprogram the SPI boot Flash. Reprogramming instructions are provided later in this document.
Table 2 – FPGA boot options
Function M2- M1 - M0 Notes
Direct FPGA programming 0 – 0 - 1 Programs FPGA (volatile)
Programs SPI Boot Flash
(default configuration)
1 – 0 - 1 Programs SPI Boot Flash (non volatile)
FPGA boots from Flash
There are two green LEDs driven by the FPGA to provide some initialization status. LED D2 lights up
when the FPGA initialization sequence is complete and asserts the DONE_0 signal high. LED D10 lights
up when the FPGA is in a configuration reset state and will turn off when the initialization is complete.
Xilinx provides a complete technical guide on the FPGA configuration sequence. See Xilinx UG470.