diff --git a/libraries/base/common/src/vhdl/common_peak.vhd b/libraries/base/common/src/vhdl/common_peak.vhd new file mode 100644 index 0000000000000000000000000000000000000000..c0bc0b907d4b1f40068efa50d13751d89d928b24 --- /dev/null +++ b/libraries/base/common/src/vhdl/common_peak.vhd @@ -0,0 +1,97 @@ +------------------------------------------------------------------------------- +-- +-- Copyright (C) 2010 +-- ASTRON (Netherlands Institute for Radio Astronomy) <http://www.astron.nl/> +-- JIVE (Joint Institute for VLBI in Europe) <http://www.jive.nl/> +-- P.O.Box 2, 7990 AA Dwingeloo, The Netherlands +-- +-- This program is free software: you can redistribute it and/or modify +-- it under the terms of the GNU General Public License as published by +-- the Free Software Foundation, either version 3 of the License, or +-- (at your option) any later version. +-- +-- This program is distributed in the hope that it will be useful, +-- but WITHOUT ANY WARRANTY; without even the implied warranty of +-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +-- GNU General Public License for more details. +-- +-- You should have received a copy of the GNU General Public License +-- along with this program. If not, see <http://www.gnu.org/licenses/>. +-- +------------------------------------------------------------------------------- + +-- Purpose: Provide the maximum value that is seen on the input on the output. +-- Description: The peak value of the input data is captured and maintained +-- on the output. A pulse on in_clear will reset thepeak value. +-- Only valid data will be considered. +-- +-- +-- +LIBRARY IEEE; +USE IEEE.std_logic_1164.ALL; +USE work.common_pkg.ALL; + +ENTITY common_peak IS + GENERIC ( + g_dat_w : POSITIVE := 8 + ); + PORT ( + rst : IN STD_LOGIC := '0'; + clk : IN STD_LOGIC; + in_dat : IN STD_LOGIC_VECTOR(g_dat_w-1 DOWNTO 0); + in_val : IN STD_LOGIC := '1'; + in_clear : IN STD_LOGIC; + out_dat : OUT STD_LOGIC_VECTOR(g_dat_w-1 DOWNTO 0); + out_val : OUT STD_LOGIC + ); +END common_peak; + +ARCHITECTURE rtl OF common_peak IS + + TYPE reg_type IS RECORD + peak : STD_LOGIC_VECTOR(g_dat_w-1 DOWNTO 0); + out_val : STD_LOGIC; + END RECORD; + + SIGNAL r, rin : reg_type; + +BEGIN + + p_comb : PROCESS(r, rst, in_val, in_dat, in_clear) + VARIABLE v : reg_type; + BEGIN + + v := r; + + IF in_val = '1' THEN + IF TO_UINT(in_dat) > TO_UINT(r.peak) THEN + v.peak := in_dat; + v.out_val := '1'; + END IF; + END IF; + + IF in_clear = '1' then + v.peak := (OTHERS => '0'); + v.out_val := '0'; + END IF; + + IF(rst = '1') THEN + v.peak := (OTHERS => '0'); + v.out_val:= '0'; + END IF; + + rin <= v; + + END PROCESS; + + p_regs : PROCESS(clk) + BEGIN + IF RISING_EDGE(clk) THEN + r <= rin; + END IF; + END PROCESS; + + out_val <= r.out_val; + out_dat <= r.peak; + +END rtl;