Subversion Repositories astron_sim_tools

-------------------------------------------------------------------------------

--

-- Copyright 2020

-- ASTRON (Netherlands Institute for Radio Astronomy) <http://www.astron.nl/>

-- P.O.Box 2, 7990 AA Dwingeloo, The Netherlands

-- 

-- Licensed under the Apache License, Version 2.0 (the "License");

-- you may not use this file except in compliance with the License.

-- You may obtain a copy of the License at

-- 

--     http://www.apache.org/licenses/LICENSE-2.0

-- 

-- Unless required by applicable law or agreed to in writing, software

-- distributed under the License is distributed on an "AS IS" BASIS,

-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

-- See the License for the specific language governing permissions and

-- limitations under the License.

--

-------------------------------------------------------------------------------

-- Purpose: Scope component to show the arrayed DP SOSI data at the SCLK

--          sample rate

-- Description:

--   The SCLK rate is g_wideband_factor faster than the DCLK rate. The input

--   is one wideband stream that is carried by an array of g_wideband_factor

--   sosi streams at the DCLK rate. The output is a single sosi integer stream

--   at the SCLK rate.

-- Remark:

-- . Only for simulation.

-- . When g_use_sclk=TRUE then the input SCLK is used. Else the SCLK is derived

--   from the DCLK so that it does not have to be applied via an input. This

--   eases the use of this scope within a design.

-- . In this dp_wideband_wb_arr_scope the input is only one wideband stream

--   and the input sosi array has size g_wideband_factor, so the wideband

--   data is carried via the sosi array dimension.

--   In dp_wideband_sp_arr_scope the input is one or more wideband streams

--   and the input sosi array has size g_nof_streams, so there the wideband

--   data is carried by g_wideband_factor concatenated symbols in the data

--   field or in the (re, im) fields.

LIBRARY IEEE, common_pkg_lib, dp_pkg_lib;

USE IEEE.STD_LOGIC_1164.ALL;

USE common_pkg_lib.common_pkg.ALL;

USE dp_pkg_lib.dp_stream_pkg.ALL;

ENTITY dp_wideband_wb_arr_scope IS

  GENERIC (

    g_sim                 : BOOLEAN := FALSE;

    g_use_sclk            : BOOLEAN := TRUE;

    g_wideband_factor     : NATURAL := 4;        -- Wideband rate factor = 4 for dp_clk processing frequency is 200 MHz frequency and SCLK sample frequency Fs is 800 MHz

    g_wideband_big_endian : BOOLEAN := FALSE;    -- When true wb_sosi_arr[3:0] = sample[t0,t1,t2,t3], else when false : wb_sosi_arr[3:0] = sample[t3,t2,t1,t0]

    g_dat_w               : NATURAL := 8         -- Actual width of the data field or of the re field, im field

  );

  PORT (

    -- Digital processing clk

    DCLK         : IN STD_LOGIC := '0';

    -- Sampling clk, for simulation only

    SCLK         : IN STD_LOGIC := '0';   -- SCLK rate = g_wideband_factor * DCLK rate

    -- Streaming input samples for one stream

    wb_sosi_arr  : IN t_dp_sosi_arr(g_wideband_factor-1 DOWNTO 0);   -- = [3:0] = Signal Path time samples [t3,t2,t1,t0]

    -- Scope output samples for one stream

    scope_sosi   : OUT t_dp_sosi_integer

  );

END dp_wideband_wb_arr_scope;

ARCHITECTURE beh OF dp_wideband_wb_arr_scope IS

  SIGNAL SCLKi        : STD_LOGIC;  -- sampling clk, for simulation only

  SIGNAL sample_cnt   : NATURAL RANGE 0 TO g_wideband_factor-1 := 0;

  SIGNAL st_sosi      : t_dp_sosi;

BEGIN

  sim_only : IF g_sim=TRUE GENERATE

    use_sclk : IF g_use_sclk=TRUE GENERATE

      SCLKi <= SCLK;  -- no worry about the delta cycle delay from SCLK to SCLKi

    END GENERATE;

    gen_sclk : IF g_use_sclk=FALSE GENERATE

      proc_common_dclk_generate_sclk(g_wideband_factor, DCLK, SCLKi);

    END GENERATE;

    -- View wb_sosi_arr at the sample rate using st_sosi

    p_st_sosi : PROCESS(SCLKi)

    BEGIN

      IF rising_edge(SCLKi) THEN

        IF g_wideband_big_endian=TRUE THEN

          st_sosi <= wb_sosi_arr(g_wideband_factor-1-sample_cnt);

        ELSE

          st_sosi <= wb_sosi_arr(sample_cnt);

        END IF;

        sample_cnt <= 0;

        IF wb_sosi_arr(0).valid='1' AND sample_cnt < g_wideband_factor-1 THEN  -- all wb_sosi_arr().valid are the same, so use (0)

          sample_cnt <= sample_cnt + 1;

        END IF;

      END IF;

    END PROCESS;

    -- Map sosi to SLV of actual g_dat_w to allow observation in Wave Window in analogue format

    scope_sosi <= func_dp_stream_slv_to_integer(st_sosi, g_dat_w);

  END GENERATE;

END beh;