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Altera_Forum
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14 years ago

Avalon-ST Multiplexer

Hello,

I am trying to do a multiconnection system to the TSE core. Hardware generated stream would go directly to the TSE and the other packets (ARP/ICMP/etc) should also go from the sgdma to TSE. In this case, I've added Avalon-ST mux, where one sink is connected with the sgdma out and the other is connected to my component output.

The datasheet of avalon-st mux (http://www.altera.com/literature/ug/ug_embedded_ip.pdf) (page19-2) says:

The multiplexer includes a simple, round-robin scheduler that selects from the next input interface that has data. Also there's mentioned, that the channel signal is optional.

However, when I set channel signal to 0, then it drops an error that it has to be greater than zero. If I set the channel to 1, then the scheduler is not working - the channel which has data is not switched to the output.

Use packet scheduling - enabled.

Use high bits to indicate source ports - disabled.

Packet support - enabled (8bits*4 words).

How do I enable automatic packet selection?

Thanks.

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    Well yes, it was created automatically between MUX and TSE. Does the output have something common in packet scheduling?

  • Altera_Forum's avatar
    Altera_Forum
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    It says in the datasheet that the valid values for number of input ports are 2-16.

  • Altera_Forum's avatar
    Altera_Forum
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    Hi, Socrates, did you find anything else squirrely with channels? I am trying to use an input of a 20-bit channel on an 8-port mux. Should be 23 bits total (Altera allows 0-31), but Quartus keeps saying it's out of range and keeps asking for 0-8 channel bits, when the Embedded IP User's guide says it should support up to 31 total.

  • Altera_Forum's avatar
    Altera_Forum
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    By the time - I wrote my own mux/scheduler and did not work out how the one from the library works.