cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
Charlycop
Observer
Observer
342 Views
Registered: ‎11-28-2020

Help with AXI Stream signals

I'm a very beginner in AXI Stream, and I need help.

Can you confirm those assertions ?

from the example : I'm waiting 1000 32bits (4 bytes) integer from the PS side.

  1. axi stream goes only in 1 direction from master to slave
  2. if I want to send data back, I need another axi stream but MASTER and add a SLAVE on my Zynq CPU
  3. tvalid signal should be 1 once my tdata in ready
  4. my IP should send tready once it's ready to receive
  5. tlast signal, should be 1 at the 1000 rising_edge
  6. tstrb signal represent the 4 bytes inside the 32 bits, and I should keep the 4 bits of the tstrb signal at 1 because its always aligned.

Thanks for your help !

Charly.

I'm using vivado 2018.3 on Windows 10 pro 20H2 with a surface pro 4, i7 CPU and 16Go or RAM.
Tags (2)
0 Kudos
2 Replies
bruce_karaffa
Scholar
Scholar
317 Views
Registered: ‎06-21-2017

What example are you referring to?  You are waiting 1000 what?  Is that 1000 clock cycles, the rising edge of a clock with a period or frequency of 1000 or are you trying to send 1000 32-bit data words?  When you have valid date, you may assert tvalid.  If tready is high, that data word is transmitted.  If tready is low, you must keep tvalid high until tready is high, then release it on the clock cycle after tready high is detected.  tlast must go high on the same clock cycle as the last data word and tvalid and must be held until tready is detected high.

Charlycop
Observer
Observer
265 Views
Registered: ‎11-28-2020

Here is the example :

from the example : I'm waiting 1000 * 32bits (4 bytes) integer from the PS side. Which means, I want to transfer 1000 * 32-bits data words.

Seems you understand the stream very well, can you tell me if those assertions are true ?

  1. axi stream goes only in 1 direction from master to slave
  2. if I want to send data back, I need another axi stream MASTER in my IP and add a axi stream SLAVE on my Zynq CPU

thanks

I'm using vivado 2018.3 on Windows 10 pro 20H2 with a surface pro 4, i7 CPU and 16Go or RAM.
0 Kudos