FPGA CI Test Shield

This project contains RTL and tests for the FPGA CI Test Shield. The FPGA CI Test Shield is a shield which can be attached to Mbed boards to allow in-depth testing of all connected pins.

Required software and hardware

Building and testing this project require the following tools and hardware:

• Vivado HL WebPACK for FPGA synthesis, implementation and programming
• iverilog for simulation testing
• GTKWave for viewing simulation waveforms
• FPGA CI Test Shield
• Any Mbed enabled board

Simulation testing

Batch files are provided to run simulation on various parts of the system. To run the tests, open a terminal in the sim directory and run the build_and_run_*.bat for the desired test. If an error occurs, it will be printed. Note - this also starts a waveform viewer at the end of the simulation.

Building and programming the FPGA image

Vivado is used to build FPGA images. The following sequence can be used to create a programmable image:

• Generate and open the project
  • Start Vivado
  • Click "Window -> Tcl Console"
  • In the Tcl console, change the current directory to that of the project > cd <project location>/fpga-ci-test-shield (for those using Windows, Vivado uses forward slashes instead of backslashes for file paths)
  • In the Tcl console, generate and open the project > source generate_project_shield.tcl
• Generate bitstream (.bit and .bin files) inside Vivado by clicking the Generate Bitstream button
• Add a CRC to the new image
  • Start command prompt in the project directory
  • Run the post process script > python post_process_bitstream.py project_shield\project_shield.runs\impl_1\mbed_tester_shield_top.bin mbed_tester_shield_top_crc.bin
• Program the bitstream file to the device using the update script and Mbed code found in the fpga-ci-test-shield-updater project.

Example greentea testcase using FPGA CI test shield

void spi_test_common(PinName mosi, PinName miso, PinName sclk, PinName ssel)
{
    printf("SPI test on mosi=%s (%i), miso=%s (%i), sclk=%s (%i), ssel=%s (%i)\r\n",
            pinmap_ff_default_pin_to_string(mosi), mosi,
            pinmap_ff_default_pin_to_string(miso), miso,
            pinmap_ff_default_pin_to_string(sclk), sclk,
            pinmap_ff_default_pin_to_string(ssel), ssel);

    // Remap pins for test
    tester.reset();
    tester.pin_map_set(mosi, MbedTester::LogicalPinSPIMosi);
    tester.pin_map_set(miso, MbedTester::LogicalPinSPIMiso);
    tester.pin_map_set(sclk, MbedTester::LogicalPinSPISclk);
    tester.pin_map_set(ssel, MbedTester::LogicalPinSPISsel);

    // Initialize mbed SPI pins
    spi_t spi;
    spi_init(&spi, mosi, miso, sclk, ssel);
    spi_format(&spi, 8, 0, 0);
    spi_frequency(&spi, 1000000);

    // Reset tester stats and select SPI
    tester.peripherals_reset();
    tester.select_peripheral(MbedTester::SPI);

    // Send and receive test data
    uint32_t checksum = 0;
    for (int i = 0; i < TRANSFER_COUNT; i++) {
        uint8_t data = spi_master_write(&spi, (0 - i) & 0xFF);
        TEST_ASSERT_EQUAL(i & 0xFF, data);

        checksum += (0 - i) & 0xFF;
    }

    // Verify that the transfer was successful
    TEST_ASSERT_EQUAL(TRANSFER_COUNT, tester.spi_transfer_count());
    TEST_ASSERT_EQUAL(checksum, tester.spi_to_slave_checksum());

    printf("  Pin combination works\r\n");

    spi_free(&spi);
    tester.reset();
}

License and contributions

The software is provided under the Apache-2.0 license. Contributions to this project are accepted under the same license. Please see contributing.md for more information.

This project contains code from other projects. The original license text is included in those source files. They must comply with our license guide.

Folders containing files under different permissive license than Apache 2.0 are listed in the LICENSE file.