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Altera_Forum's avatar
Altera_Forum
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9 years ago

Getting access to HPS GPIO lines

I am working on a Cyclone V project: part 5CSEBA5U23C8SN

I am using the HPS configured with the following:

SDRAM

1 Uart (uart0, HPS IO Set 0)

Ethernet (EMAC1, HPS IO Set 0, RGMII)

SD/MMC controller (4 bit data, HPS IO SET 0)

Two SPI Masters, both on HPS IO Set 0

1 I2C controller, HPS IO Set 0

The following peripherals were set to "UNUSED"

Nand Flash

QSPI Controller

USB Controller

UART1

I2C 1,2,3

Can Controller

Trace port

I was expecting to have access to significant number of GPIO pins, but I am only getting 6:

hps_0_hps_io_hps_io_gpio_inst_GPIO09,

hps_0_hps_io_hps_io_gpio_inst_GPIO35,

hps_0_hps_io_hps_io_gpio_inst_GPIO41,

hps_0_hps_io_hps_io_gpio_inst_GPIO42,

hps_0_hps_io_hps_io_gpio_inst_GPIO43,

hps_0_hps_io_hps_io_gpio_inst_GPIO44,

Why aren't the other unused pins available?

For example: GPIO48 is associated with TRACE_CLK and nothing else. Why isn't it available as GPIO?

GPIO29 is associated with the QSPI controller or USB, neither of which is used and it is not being made available.

Thanks.

Rod

3 Replies

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

    Hello, in the Qsys HPS Component, did you click on the "GPIO" for every HPS I/O that is not assigned to other peripherals (the current assignment of the pin is highlighted in bold. If it is not used for any peripheral, you can click the GPIO function to assign it as GPIO)

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

    Ah, thank you!

    And now I see how to get access to the unused HPS pins for general FPGA work! Thank you very much!

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

    --- Quote Start ---

    Ah, thank you!

    And now I see how to get access to the unused HPS pins for general FPGA work! Thank you very much!

    Rod

    --- Quote End ---

    Glad to hear that :)