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Altera_Forum's avatar
Altera_Forum
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9 years ago

fast input registers routed over HPS Loan I/O Pins

Hi,

I have a Cyclone V SE with a design that includes an SDIO Host Controller IP in order to attach an SDIO WiFi-Module to the System.

The SDIO Host Controller IP needs fast input registers. When I try to route the SDIO signals over HPS Loan I/O Pins, Quartus Fitter ignores the 'fast input register' settings for SDIO CMD, SDIO_DAT[3..0].

Is there any way I can use fast input registers with HPS Loan I/O Pins?

Best regards,

Tobias

1 Reply

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

    In Cyclone/Arria V the loan I/O have fewer features. The I/O registers are not present which is why loan I/O are not recommended for high speed interfaces. The HPS peripherals are registered but they do not rely on the register stage in the I/O and implement their own instead. These I/O also lack DDR capabilities so you can't route other things like a TSE out to them.