CPLD Normal: Dropped sp_default and made more similar to alternative

Change-Id: Idd72c5478b49bd2977b49b8a3640ed243c259ac9
issue_1022
David Banks 2018-06-09 11:33:01 +01:00
rodzic 7396747665
commit 9dd59b9990
2 zmienionych plików z 134 dodań i 104 usunięć

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@ -1,12 +1,12 @@
----------------------------------------------------------------------------------
-- Engineer: David Banks
--
-- Create Date: 14/4/2017
-- Create Date: 9/6/2018
-- Module Name: RGBtoHDMI CPLD
-- Project Name: RGBtoHDMI
-- Target Devices: XC9572XL
--
-- Version: 0.50
-- Version: 0.9
--
----------------------------------------------------------------------------------
library ieee;
@ -54,14 +54,16 @@ architecture Behavorial of RGBtoHDMI is
constant default_offset : unsigned(11 downto 0) := to_unsigned(4096 - 64 * 17 + 6, 12);
-- For Mode 7
constant mode7_offset : unsigned(11 downto 0) := to_unsigned(4096 - 96 * 12 + 4, 12);
constant mode7_offset : unsigned(11 downto 0) := to_unsigned(4096 - 96 * 12 + 4, 12);
-- Sampling points
constant INIT_SAMPLING_POINTS : std_logic_vector(20 downto 0) := "011011011011011011011";
constant INIT_SAMPLING_POINTS : std_logic_vector(17 downto 0) := "011011011011011011";
signal shift : std_logic_vector(11 downto 0);
signal shift_R : std_logic_vector(3 downto 0);
signal shift_G : std_logic_vector(3 downto 0);
signal shift_B : std_logic_vector(3 downto 0);
signal CSYNC1 : std_logic;
signal CSYNC1 : std_logic;
-- The sampling counter runs at 96MHz
-- - In modes 0..6 it is 6x the pixel clock
@ -74,45 +76,43 @@ architecture Behavorial of RGBtoHDMI is
-- 4. Handles double buffering of alternative quad pixels (bit 5)
--
-- At the moment we don't count pixels with the line, the Pi does that
signal counter : unsigned(11 downto 0);
signal counter : unsigned(11 downto 0);
-- Sample point register;
--
-- In Modes 0..6 each pixel lasts 6 clocks (96MHz / 16MHz). The original
-- pixel clock is a clean 16Mhz clock, so only one sample point is needed.
--
-- In Mode 7 each pixel lasts 8 clocks (96MHz / 12MHz). The original
-- pixel clock is a regenerated 6Mhz clock, and both edges are used.
-- Due to the way it is generated, there are three distinct phases,
-- hence three sampling points are used.
signal sp_reg : std_logic_vector(20 downto 0) := INIT_SAMPLING_POINTS;
-- each with different rising/falling edge speeds, hence six sampling
-- points are used.
--
-- In Modes 0..6 each pixel lasts 6 clocks (96MHz / 16MHz). The original
-- pixel clock is a clean 16Mhz clock, so only one sample point is needed.
-- To achieve this, all six values are set to be the same. This minimises
-- the logic in the CPLD.
signal sp_reg : std_logic_vector(17 downto 0) := INIT_SAMPLING_POINTS;
-- Break out of sp
signal sp : std_logic_vector(2 downto 0);
signal mode7_sp_A : std_logic_vector(2 downto 0);
signal mode7_sp_B : std_logic_vector(2 downto 0);
signal mode7_sp_C : std_logic_vector(2 downto 0);
signal mode7_sp_D : std_logic_vector(2 downto 0);
signal mode7_sp_E : std_logic_vector(2 downto 0);
signal mode7_sp_F : std_logic_vector(2 downto 0);
signal default_sp : std_logic_vector(2 downto 0);
-- Break out of sp_reg
signal offset_A : std_logic_vector(2 downto 0);
signal offset_B : std_logic_vector(2 downto 0);
signal offset_C : std_logic_vector(2 downto 0);
signal offset_D : std_logic_vector(2 downto 0);
signal offset_E : std_logic_vector(2 downto 0);
signal offset_F : std_logic_vector(2 downto 0);
-- Index to allow cycling between A, B and C in Mode 7
signal sp_index : std_logic_vector(2 downto 0);
-- Pipelined offset mux output
signal offset : std_logic_vector(2 downto 0);
-- Index to cycle through offsets A..F
signal index : std_logic_vector(2 downto 0);
-- Sample pixel on next clock; pipelined to reduce the number of product terms
signal sample : std_logic;
signal sample : std_logic;
-- Load quad on next clock; pipelined to reduce the number of product terms
signal load : std_logic;
-- Toggle on each quad loading
signal toggle : std_logic;
signal R : std_logic;
signal G : std_logic;
signal B : std_logic;
-- RGB Input Mux
signal R : std_logic;
signal G : std_logic;
signal B : std_logic;
begin
@ -120,19 +120,16 @@ begin
G <= G1 when elk = '1' else G0;
B <= B1 when elk = '1' else B0;
mode7_sp_A <= sp_reg(2 downto 0);
mode7_sp_B <= sp_reg(5 downto 3);
mode7_sp_C <= sp_reg(8 downto 6);
mode7_sp_D <= sp_reg(11 downto 9);
mode7_sp_E <= sp_reg(14 downto 12);
mode7_sp_F <= sp_reg(17 downto 15);
default_sp <= sp_reg(20 downto 18);
offset_A <= sp_reg(2 downto 0);
offset_B <= sp_reg(5 downto 3);
offset_C <= sp_reg(8 downto 6);
offset_D <= sp_reg(11 downto 9);
offset_E <= sp_reg(14 downto 12);
offset_F <= sp_reg(17 downto 15);
-- Shift the bits in LSB first
process(sp_clk, SW1)
begin
--if SW1 = '0' then
-- sp_reg <= INIT_SAMPLING_POINTS;
if rising_edge(sp_clk) then
if sp_clken = '1' then
sp_reg <= sp_data & sp_reg(sp_reg'left downto sp_reg'right + 1);
@ -143,23 +140,10 @@ begin
process(clk)
begin
if rising_edge(clk) then
-- synchronize CSYNC to the sampling clock
CSYNC1 <= S;
-- quad load
if counter(4 downto 0) = "00000" then
load <= '1';
else
load <= '0';
end if;
-- sample shift
if counter(2 downto 0) = unsigned(sp) then
sample <= '1';
else
sample <= '0';
end if;
-- Counter is used to find sampling point for first pixel
if CSYNC1 = '0' then
if mode7 = '1' then
@ -170,63 +154,98 @@ begin
elsif counter(11) = '1' then
counter <= counter + 1;
elsif mode7 = '1' or counter(2 downto 0) /= 5 then
counter(4 downto 0) <= counter(4 downto 0) + 1;
counter(5 downto 0) <= counter(5 downto 0) + 1;
else
counter(4 downto 0) <= counter(4 downto 0) + 3;
counter(5 downto 0) <= counter(5 downto 0) + 3;
end if;
-- Sample point offsets
-- Sample point offset index
if CSYNC1 = '0' then
sp_index <= "000";
if mode7 = '1' then
sp <= mode7_sp_A;
else
sp <= default_sp;
index <= "000";
else
-- so index offset changes at the same time counter wraps 7->0
if counter(2 downto 0) = 6 then
case index is
when "000" =>
index <= "001";
when "001" =>
index <= "010";
when "010" =>
index <= "011";
when "011" =>
index <= "100";
when "100" =>
index <= "101";
when others =>
index <= "000";
end case;
end if;
elsif mode7 = '1' and counter(2 downto 0) = 7 then
-- within the line
case sp_index is
when "000" =>
sp_index <= "001";
sp <= mode7_sp_B;
when "001" =>
sp_index <= "010";
sp <= mode7_sp_C;
when "010" =>
sp_index <= "011";
sp <= mode7_sp_D;
when "011" =>
sp_index <= "100";
sp <= mode7_sp_E;
when "100" =>
sp_index <= "101";
sp <= mode7_sp_F;
when others =>
sp_index <= "000";
sp <= mode7_sp_A;
end case;
end if;
-- Sample/shift registers
if counter(11) = '0' and sample = '1' then
shift <= B & G & R & shift(11 downto 3);
-- Sample point offset
case index is
when "000" =>
offset <= offset_B;
when "001" =>
offset <= offset_C;
when "010" =>
offset <= offset_D;
when "011" =>
offset <= offset_E;
when "100" =>
offset <= offset_F;
when others =>
offset <= offset_A;
end case;
-- sample/shift control
if counter(11) = '0' and counter(2 downto 0) = unsigned(offset) then
sample <= '1';
else
sample <= '0';
end if;
-- R Sample/shift register
if sample = '1' then
shift_R <= R & shift_R(3 downto 1);
end if;
-- G Sample/shift register
if sample = '1' then
shift_G <= G & shift_G(3 downto 1);
end if;
-- B Sample/shift register
if sample = '1' then
shift_B <= B & shift_B(3 downto 1);
end if;
-- Output quad register
if counter(11) = '0' then
if load = '1' then
quad <= shift;
toggle <= not toggle;
if counter(4 downto 0) = "00000" then
quad(11) <= shift_B(3);
quad(10) <= shift_G(3);
quad(9) <= shift_R(3);
quad(8) <= shift_B(2);
quad(7) <= shift_G(2);
quad(6) <= shift_R(2);
quad(5) <= shift_B(1);
quad(4) <= shift_G(1);
quad(3) <= shift_R(1);
quad(2) <= shift_B(0);
quad(1) <= shift_G(0);
quad(0) <= shift_R(0);
psync <= counter(5);
end if;
else
quad <= (others => '0');
toggle <= '0';
quad <= (others => '0');
psync <= '0';
end if;
end if;
end process;
psync <= toggle;
csync <= S; -- pass through, as clock might not be running
LED1 <= 'Z'; -- allow this to be driven from the Pi
LED2 <= not(mode7);

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@ -219,3 +219,14 @@ FB3 18/18* 30/54 45/90 8/ 9
FB4 18/18* 37/54 63/90 7/ 7*
----- ----- ----- -----
70/72 126/216 206/360 29/34
19. Dropped seperate sp_default stage
Function Mcells FB Inps Pterms IO
Block Used/Tot Used/Tot Used/Tot Used/Tot
FB1 18/18* 30/54 42/90 5/ 9
FB2 17/18 25/54 34/90 9/ 9*
FB3 18/18* 29/54 55/90 8/ 9
FB4 13/18 35/54 44/90 7/ 7*
----- ----- ----- -----
66/72 119/216 175/360 29/34