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- Cleaned up

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git-svn-id: http://moon:8086/svn/vhdl/trunk@145 cc03376c-175c-47c8-b038-4cd826a8556b
This commit is contained in:
jens
2008-12-21 19:53:00 +00:00
parent bf78b1beef
commit 50af9fe70d
1 changed files with 39 additions and 94 deletions
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lib/radio/nco/src/nco_cordic.vhd
+38 -93
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@@ -22,6 +22,7 @@ use IEEE.STD_LOGIC_1164.ALL;
use IEEE.MATH_REAL.ALL; use IEEE.MATH_REAL.ALL;
USE ieee.numeric_std.ALL; USE ieee.numeric_std.ALL;
use work.fixed_pkg.all; use work.fixed_pkg.all;
use work.cordic_pkg.all;
use work.nco_pkg.all; use work.nco_pkg.all;
---- Uncomment the following library declaration if instantiating ---- Uncomment the following library declaration if instantiating
@@ -33,13 +34,7 @@ entity nco is
Generic Generic
( (
nbits_wave : integer := 18; nbits_wave : integer := 18;
nbits_phase : integer := 16; nbits_phase : integer := 16
nbits_lut_depth : integer := 12;
nbits_dither : integer := 4;
nbits_lfsr : integer := 12;
q_phase : phase_relation_t := phase_90deg;
has_pipe_reg : boolean := false;
has_out_reg : boolean := false
); );
Port Port
( (
@@ -65,6 +60,7 @@ architecture Behavioral of nco is
( (
cordic_mode : cordic_mode_t; cordic_mode : cordic_mode_t;
z_range : real; z_range : real;
gain_corr_mode : gain_corr_mode_t;
nstages : integer; nstages : integer;
nbits_x_in : integer; nbits_x_in : integer;
nbits_y_in : integer; nbits_y_in : integer;
@@ -95,78 +91,41 @@ architecture Behavioral of nco is
END COMPONENT; END COMPONENT;
------------------------------------------------------------------------------- -------------------------------------------------------------------------------
constant nbits_wave_frac : integer := nbits_wave; constant nbits_wave_frac : integer := nbits_wave-1;
constant nbits_phase_frac : integer := nbits_phase;
------------------------------------------------------------------------------- -------------------------------------------------------------------------------
constant lfsr_gen_poly : unsigned(nbits_lfsr-1 downto 0) := to_unsigned(lfsr_poly(nbits_lfsr), nbits_lfsr); -- 24 signal phase : signed(nbits_phase-1 downto 0);
signal freq_in_r : signed(nbits_phase-1 downto 0);
signal phase_in_r : signed(nbits_phase-1 downto 0);
signal wave_i_ud, wave_q_ud : sfixed(shi(nbits_wave, nbits_wave_frac) downto slo(nbits_wave, nbits_wave_frac));
signal phase : unsigned(nbits_phase-1 downto 0); signal wave_ud_valid, phase_vld : std_logic;
signal freq_in_r : unsigned(nbits_phase-1 downto 0);
signal phase_in_r : unsigned(nbits_phase-1 downto 0);
signal lut_addr_d : unsigned(nbits_lut_depth-1 downto 0);
signal wave_i_d, wave_q_d : sfixed(shi(nbits_wave, nbits_wave_frac) downto slo(nbits_wave, nbits_wave_frac));
type lfsr_t is array (0 to 1) of unsigned(nbits_lfsr-1 downto 0); signal zin_ud : sfixed(shi(nbits_phase, nbits_phase_frac) downto slo(nbits_phase, nbits_phase_frac));
signal lfsr : lfsr_t; signal xin : sfixed(shi(nbits_wave, nbits_wave_frac) downto slo(nbits_wave, nbits_wave_frac)) := to_sfixed(0.0, shi(nbits_wave, nbits_wave_frac), slo(nbits_wave, nbits_wave_frac));
signal lfsr_out : unsigned(nbits_dither-1 downto 0); signal yin :sfixed(shi(nbits_wave, nbits_wave_frac) downto slo(nbits_wave, nbits_wave_frac)) := to_sfixed(1.0, shi(nbits_wave, nbits_wave_frac), slo(nbits_wave, nbits_wave_frac));
signal lut_addr_valid, lfsr_valid, wave_d_valid : std_logic;
signal zin : sfixed(shi(nbits_lut_depth, nbits_lut_depth) downto slo(nbits_lut_depth, nbits_lut_depth));
signal xin : sfixed(shi(nbits_wave, nbits_wave_frac) downto slo(nbits_wave, nbits_wave_frac)) := to_sfixed(0.0, shi(nbits_x_in, nbits_frac_x_in), slo(nbits_x_in, nbits_frac_x_in));
signal yin :sfixed(shi(nbits_wave, nbits_wave_frac) downto slo(nbits_wave, nbits_wave_frac)) := to_sfixed(1.0, shi(nbits_y_in, nbits_frac_y_in), slo(nbits_y_in, nbits_frac_y_in));
signal zout_ud : sfixed(shi(nbits_phase, nbits_phase_frac) downto slo(nbits_phase, nbits_phase_frac));
------------------------------------------------------------------------------- -------------------------------------------------------------------------------
begin begin
wave_out_i <= wave_i_d; wave_out_i <= wave_i_ud;
wave_out_q <= wave_q_d; wave_out_q <= wave_q_ud;
out_valid <= wave_d_valid; out_valid <= wave_ud_valid;
z_in <= to_sfixed(signed(lut_addr_d), z_in);
------------------------------------------------------------ ------------------------------------------------------------
proc_lfsr: process(srst, clk, lfsr, pacc_inc) proc_phase_accu: process(srst, clk, pacc_clr, pacc_inc, freq_in_r, phase_in_r)
variable lo : unsigned(nbits_dither-1 downto 0); variable phase_accu : signed(nbits_phase-1 downto 0);
begin
if rising_edge(clk) then
if srst = '1' then
lfsr_valid <= '0';
lfsr_out <= (others => '0');
for i in lfsr'range loop
lfsr(i) <= to_unsigned(2**i, nbits_lfsr);
end loop;
else
lfsr_valid <= '0';
if pacc_inc ='1' then
lfsr_valid <= '1';
lo := (others => '0');
for i in lfsr'range loop
if lfsr(i)(lfsr(i)'left) = '1' then
lfsr(i) <= (lfsr(i)(lfsr(i)'left-1 downto 0) & lfsr(i)(lfsr(i)'left)) xor lfsr_gen_poly;
else
lfsr(i) <= lfsr(i)(lfsr(i)'left-1 downto 0) & lfsr(i)(lfsr(i)'left);
end if;
end loop;
for i in lfsr'range loop
lo := lo + lfsr(i)(nbits_dither-1 downto 0);
end loop;
-- lo := lfsr(0)(nbits_dither downto 0);
lfsr_out <= lo(nbits_dither-1 downto 0);
end if;
end if;
end if;
end process;
------------------------------------------------------------
proc_phase_accu: process(clk, phase)
variable phase_accu : unsigned(nbits_phase-1 downto 0);
begin begin
if rising_edge(clk) then if rising_edge(clk) then
phase_vld <= '0';
if srst = '1' then if srst = '1' then
phase_accu := (others => '0'); phase_accu := (others => '0');
else else
phase_vld <= '1';
phase <= phase_accu + phase_in_r; phase <= phase_accu + phase_in_r;
if pacc_clr = '1' then if pacc_clr = '1' then
phase_accu := (others => '0'); phase_accu := (others => '0');
@@ -175,7 +134,8 @@ begin
end if; end if;
end if; end if;
end if; end if;
phase_out <= phase; phase_out <= unsigned(phase);
zin_ud <= sfixed(phase);
end process; end process;
------------------------------------------------------------ ------------------------------------------------------------
@@ -185,7 +145,7 @@ begin
if srst = '1' then if srst = '1' then
freq_in_r <= (others => '0'); freq_in_r <= (others => '0');
elsif freq_load = '1' then elsif freq_load = '1' then
freq_in_r <= freq_in; freq_in_r <= signed(freq_in);
end if; end if;
end if; end if;
end process; end process;
@@ -197,59 +157,44 @@ begin
if srst = '1' then if srst = '1' then
phase_in_r <= (others => '0'); phase_in_r <= (others => '0');
elsif phase_load = '1' then elsif phase_load = '1' then
phase_in_r <= phase_in; phase_in_r <= signed(phase_in);
end if; end if;
end if; end if;
end process; end process;
------------------------------------------------------------ ------------------------------------------------------------
proc_pipe_reg: process(clk) inst_cordic_ud: cordic_pipe_top
variable lfsr_sum : unsigned(nbits_phase-1 downto 0);
begin
if rising_edge(clk) then
lut_addr_valid <= '0';
if srst = '1' then
lfsr_sum := (others => '0');
elsif lfsr_valid = '1' then
lut_addr_valid <= '1';
lfsr_sum := lfsr_out + phase;
end if;
end if;
lut_addr_d <= lfsr_sum(nbits_phase-1 downto nbits_phase-nbits_lut_depth);
end process;
------------------------------------------------------------
inst_cordic: cordic_pipe_top
GENERIC MAP GENERIC MAP
( (
cordic_mode => cordic_mode_rotate, cordic_mode => cordic_mode_rotate,
z_range => 1.0, z_range => 1.0,
nstages => 18, gain_corr_mode => gain_mode_disabled,
nstages => nbits_phase,
nbits_x_in => nbits_wave, nbits_x_in => nbits_wave,
nbits_frac_x_in => nbits_wave_frac, nbits_frac_x_in => nbits_wave_frac,
nbits_y_in => nbits_wave, nbits_y_in => nbits_wave,
nbits_frac_y_in => nbits_wave_frac, nbits_frac_y_in => nbits_wave_frac,
nbits_z_in => nbits_lut_depth, nbits_z_in => nbits_phase,
nbits_frac_z_in => nbits_lut_depth-2, nbits_frac_z_in => nbits_phase_frac,
nbits_x_out => nbits_wave, nbits_x_out => nbits_wave,
nbits_frac_x_out => nbits_wave_frac, nbits_frac_x_out => nbits_wave_frac,
nbits_y_out => nbits_wave, nbits_y_out => nbits_wave,
nbits_frac_y_out => nbits_wave_frac, nbits_frac_y_out => nbits_wave_frac,
nbits_z_out => nbits_lut_depth, nbits_z_out => nbits_phase,
nbits_frac_z_out => nbits_lut_depth-2 nbits_frac_z_out => nbits_phase_frac
) )
PORT MAP PORT MAP
( (
rst => srst, rst => srst,
clk => clk, clk => clk,
vld_in => lut_addr_valid, vld_in => phase_vld,
xin => xin, xin => xin,
yin => yin, yin => yin,
zin => zin, zin => zin_ud,
xout => wave_i_d, xout => wave_i_ud,
yout => wave_q_d, yout => wave_q_ud,
zout => open, zout => zout_ud,
vld_out => wave_d_valid vld_out => wave_ud_valid
); );
------------------------------------------------------------ ------------------------------------------------------------