Dear all, I am reading the RFNoC Specification PDF (version 0.7), and I have several questions. Any help is appreciated.
1. In AXI-Stream Data (2.3.3.3), axis_data_clk is provided. However, some blocks use ce_clk instead. Why? In [1] it is stated: "Many other blocks require the ce (Compute Engine) clock, which is used for the block's internal DSP". However, I cannot see any "internal DSP" in rfnoc_keep_one_in_n.v. In which case should I prefer ce_clk? 2. In AXI-Stream Data (2.3.3.3), I have no control over CHDR header. What happens when the block drop samples (e.g. keep_one_in_n.v)? Is the NoC Shell updating header field automatically (eg. length field)? 2bis. What happends if I drop all samples of a packet? 3.In rfnoc_keep_one_in_n.v, it seems that it drops the timestamp if the sample to keep is not the first sample in the packet. Is the timestamp recomputed afterwards? If not, how could I compute the timestamp instead of dropping it? 4. In NoC Shell Generation Options (2.3.3.4), there are some fifo parameters (e.g. info_fifo_depth). What are their purposes? How should I choose a depth value? 5. In AXI-Stream Payload Context (2.3.3.2), it is stated: "NIPC: The number of items delivered per cycle. NIPC must 1 or a larger power of 2, such that ITEM_W * NIPC = CHDR_W." Does it also apply for AXI-Stream Data (2.3.3.3)? If not, what is the rule for that Data-Plane ? In Input Format (4.2), the following keys are not documented: - sw_iface (nocscript, c++) - mdata_sig (~, MD5 sum) 6. Is the nocscript meaning we have to rely on the UHD C++ RFNoC API to interact with blocks and the c++ meaning we implement a custom C++ API? 7. What is mdata_sig? 8. Keys "registers" and "properties" seem unused, should I use them? 9. In Figure 16 (4.2), I was unable to find how to use RFNoC ModTool with a YAML file. Is it not implemented yet? [1] https://kb.ettus.com/Getting_Started_with_RFNoC_in_UHD_4.0#Understanding_the_RFNoC_Image_YAML_File Kind regards Cédric Hannotier _______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
