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Altera_Forum's avatar
Altera_Forum
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13 years ago

banks and gpio and ports

I noticed that the Cyclone III has banks and the pins are labeled IO and list other functions.....

Are the gpio pins assignable or assigned to a port like a 8 bit or 16 bit port ? I am used to programming pic microchip where each GPIO pin is assigned to a port (ex LATA, PORTD, PORTA)

Are all the gpio pins independently assignable to my own specified port or are they split into 8+ bit ports on each bank ?

Thanks

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    Sure. Any pio pin is freely assignable to any general purpose I/O pin.

    You are neither required to route all N signals of a N-bit pio port to the same i/o bank
  • Altera_Forum's avatar
    Altera_Forum
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    the I/Os are essentially independent. there are exceptions when doing wide, high speed buses like RAM interfaces and LVDS buses

  • Altera_Forum's avatar
    Altera_Forum
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    what is the top speed attainable by an assigned pin if the code was strobing it?

  • Altera_Forum's avatar
    Altera_Forum
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    You find such information in the device datasheet, although this will be an upper limit.

    The maximum switching frequency is actually limited by some design specific aspects; for example the selected i/o standard and slew rate strength, external capacitive loading.