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Altera_Forum's avatar
Altera_Forum
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13 years ago

PS Config using SPI EEPROM

I am working on a project using a Cyclone III device. I have the board setup to use an EPCS4 to configure the FPGA. The EPCS4 is programmed by a byte blaster.

The EPCS4 is very expensive. The design also includes a relatively fast ARM microcontroller. I would like to add the option of configuring the FPGA via an EEPROM, read by the microcontroller.

I see figure 9-14 (page 193) here:

http://www.altera.com/literature/hb/cyc3/cyclone3_handbook.pdf

It looks like that describes a memory device that is BIT ADDRESSABLE, with the bit going to the data[0] pin of the FPGA.

I would like to use a serial (SPI or I2C) EEPROM, these are byte addressable.

Is it feasible to read bytes from the EEPROM and use another pin from the microcontroller to produce the data[0] bitstream? (Other microcontroller pins would produce/read the other necessary signals)

Thanks!

Rich

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    --- Quote Start ---

    The EPCS4 is very expensive.

    --- Quote End ---

    The EPCS device is simply a re-branded SPI flash. You can use devices from Numonyx and Spansion in place of the EPCS devices. Search the archives for other threads.

    --- Quote Start ---

    Is it feasible to read bytes from the EEPROM and use another pin from the microcontroller to produce the data[0] bitstream? (Other microcontroller pins would produce/read the other necessary signals)

    --- Quote End ---

    Yes. Its a pretty standard method of configuring an FPGA. Here's some notes on how to do it with another FPGA or CPLD

    http://www.ovro.caltech.edu/~dwh/carma_board/fpga_configuration.pdf

    But bit-banging with a microcontroller, or wiring the SPI port to the FPGA could be used to achieve the same thing.

    Cheers,

    Dave