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Altera_Forum's avatar
Altera_Forum
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20 years ago

Problems on connecting NIOS to CS8900

Hi,

Now I'm designing a NIOS Kit with CS8900 chip. I use the CS8900 interface in the SOPC Builder directly, and I'm confuse with the byteenable[1..0] pin, 'cause there isn't any byteenale pins on the CS8900. Do I connect them to the AEN or SBHE pin on the chip, and how?

btw, I connect the address signals 3..1 on nios to the address SA3 SA2 SA1 on the CS8900, It's that right?

Thanks.

2 Replies

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

    Hello Simonhdl,

    I am assuming that you have created CS8900 with its own bus in SOPC builder.

    If so then connect AEN to ground and connect byteenable[1] to SBHE.

    If you are using NIOS configured for 32bits then you would connect the address as follows;

    Nios Address CS8900

    A2 A0

    A3 A1

    A4 A2

    Good Luck!
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    20 years ago

    Thanks, but I still confuse with the Address line.

    In CS8900, it use A1,A2,A3 to access the registers, so does the Nios Address line connect like this :

    Nios CS8900

    A2 -> A1

    A3 -> A2

    A4 -> A3

    not the A0, A1,A2 in CS8900??

    Thanks.