Hello,

I am working with RFNoC and trying to better understand how sample data is 
actually delivered over CHDR after the Radio + DDC block, particularly in terms 
of **packet spacing vs. bus rate**.

My assumption is:

* The RF chain (Radio + DDC) outputs samples at a configured sample rate, e.g., 
250 KHz.

* RFNoC groups samples into packets of SPP samples (for example, 64 samples per 
CHDR packet).

* When a packet is produced, it is transmitted across the RFNoC fabric at the 
**fabric clock rate** (e.g., 200 MHz), meaning the packet data appears as a 
short **burst** of consecutive valid cycles.

* After that burst, there is a gap (idle time) until enough samples are 
accumulated to form the next packet.

So, for example, at:

* Fs = 250 kS/s

* SPP = 64

Then we would expect:

* One packet every 64 / 250k = 256 µs

* Packet burst duration = 64 cycles at 200 MHz ≈ 320 ns

* Approximately 256 µs – 320 ns of idle time before the next packet.

### My questions are:

1. Is this understanding correct?

2. Is RFNoC guaranteed to behave this way, or can buffering cause multiple 
packets to be sent back-to-back with no idle gap?

3. Is there any official documentation describing packetization timing behavior 
of Radio/DDC  RFNoC fabric?

Thanks in advance!
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