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repo2/common/zpu/zpu_config_regs.vhdl @ 1476

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---------------------------------------------------------------------------
-- (c) 2013 mark watson
-- I am happy for anyone to use this for non-commercial use.
-- If my vhdl files are used commercially or otherwise sold,
-- please contact me for explicit permission at scrameta (gmail).
-- This applies for source and binary form and derived works.
---------------------------------------------------------------------------
LIBRARY ieee;
USE ieee.std_logic_1164.all;
use ieee.numeric_std.all;
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use IEEE.STD_LOGIC_MISC.all;
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ENTITY zpu_config_regs IS
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GENERIC
(
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platform : integer := 1; -- So ROM can detect which type of system...
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spi_clock_div : integer := 4; -- Quite conservative by default - probably want to use 1 with 28MHz input clock, 2 for 57MHz input clock, 4 for 114MHz input clock etc
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usb : integer :=0; -- USB host slave instances
nMHz_clock_div : integer -- divide the nMHz clock by n to get 1MHz
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);
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PORT
(
CLK : IN STD_LOGIC;
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RESET_N : IN STD_LOGIC;
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POKEY_ENABLE : in std_logic;
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ADDR : IN STD_LOGIC_VECTOR(10 DOWNTO 0);
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CPU_DATA_IN : IN STD_LOGIC_VECTOR(31 DOWNTO 0);
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RD_EN : IN STD_LOGIC;
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WR_EN : IN STD_LOGIC;

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-- GENERIC INPUT REGS (need to synchronize upstream...)
IN1 : in std_logic_vector(31 downto 0);
IN2 : in std_logic_vector(31 downto 0);
IN3 : in std_logic_vector(31 downto 0);
IN4 : in std_logic_vector(31 downto 0);
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-- GENERIC OUTPUT REGS
OUT1 : out std_logic_vector(31 downto 0);
OUT2 : out std_logic_vector(31 downto 0);
OUT3 : out std_logic_vector(31 downto 0);
OUT4 : out std_logic_vector(31 downto 0);
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OUT5 : out std_logic_vector(31 downto 0);
OUT6 : out std_logic_vector(31 downto 0);
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OUT7 : out std_logic_vector(31 downto 0);
OUT8 : out std_logic_vector(31 downto 0);
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-- change clock support
PLL_WRITE : out std_logic;
PLL_DATA : out std_logic_vector(31 downto 0);
PLL_ADDR : out std_logic_vector(7 downto 2);
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-- SPI
SPI_CLK : out std_logic;
SPI_DO : out std_logic;
SPI_DI : in std_logic;
SPI_SELECT0 : out std_logic;
SPI_SELECT1 : out std_logic;
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-- SD DMA
sd_addr : out std_logic_vector(15 downto 0);
sd_data : out std_logic_vector(7 downto 0);
sd_write : out std_logic;
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-- ATARI interface (in future we can also turbo load by directly hitting memory...)
SIO_DATA_IN : out std_logic;
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SIO_COMMAND : in std_logic;
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SIO_DATA_OUT : in std_logic;
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SIO_CLK_OUT : in std_logic;
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-- CPU interface
DATA_OUT : OUT STD_LOGIC_VECTOR(31 DOWNTO 0);
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PAUSE_ZPU : out std_logic;

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-- 1MHz clock (multiple)
CLK_nMHz : in std_logic;

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-- USB host
CLK_USB : in std_logic;

USBWireVPin :in std_logic_vector(usb-1 downto 0);
USBWireVMin :in std_logic_vector(usb-1 downto 0);
USBWireVPout :out std_logic_vector(usb-1 downto 0);
USBWireVMout :out std_logic_vector(usb-1 downto 0);
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USBWireOE_n :out std_logic_vector(usb-1 downto 0);

-- I2C (400k)
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i2c0_sda_in : in std_logic;
i2c0_scl_in : in std_logic;
i2c0_sda_wen : out std_logic;
i2c0_scl_wen : out std_logic;

i2c1_sda_in : in std_logic;
i2c1_scl_in : in std_logic;
i2c1_sda_wen : out std_logic;
i2c1_scl_wen : out std_logic
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);
END zpu_config_regs;

ARCHITECTURE vhdl OF zpu_config_regs IS
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component usbHostCyc2Wrap_usb1t11
port (
clk_i :in std_logic;
rst_i :in std_logic;
address_i : in std_logic_vector(7 downto 0);
data_i : in std_logic_vector(7 downto 0);
data_o : out std_logic_vector(7 downto 0);
we_i :in std_logic;
strobe_i :in std_logic;
ack_o :out std_logic;
irq :out std_logic;
usbClk :in std_logic;

USBWireVPin :in std_logic;
USBWireVMin :in std_logic;
USBWireVPout :out std_logic;
USBWireVMout :out std_logic;
USBWireOE_n :out std_logic;
USBFullSpeed :out std_logic
);
end component;

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function vectorize(s: std_logic) return std_logic_vector is
variable v: std_logic_vector(0 downto 0);
begin
v(0) := s;
return v;
end;

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signal device_decoded : std_logic_vector(7 downto 0);
signal device_wr_en : std_logic_vector(7 downto 0);
signal device_rd_en : std_logic_vector(7 downto 0);
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signal addr_decoded : std_logic_vector(31 downto 0);
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signal out1_next : std_logic_vector(31 downto 0);
signal out1_reg : std_logic_vector(31 downto 0);
signal out2_next : std_logic_vector(31 downto 0);
signal out2_reg : std_logic_vector(31 downto 0);
signal out3_next : std_logic_vector(31 downto 0);
signal out3_reg : std_logic_vector(31 downto 0);
signal out4_next : std_logic_vector(31 downto 0);
signal out4_reg : std_logic_vector(31 downto 0);
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signal out5_next : std_logic_vector(31 downto 0);
signal out5_reg : std_logic_vector(31 downto 0);
signal out6_next : std_logic_vector(31 downto 0);
signal out6_reg : std_logic_vector(31 downto 0);
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signal out7_next : std_logic_vector(31 downto 0);
signal out7_reg : std_logic_vector(31 downto 0);
signal out8_next : std_logic_vector(31 downto 0);
signal out8_reg : std_logic_vector(31 downto 0);
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signal spi_miso : std_logic;
signal spi_mosi : std_logic;
signal spi_busy : std_logic;
signal spi_enable : std_logic;
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signal spi_chip_select : std_logic_vector(1 downto 0);
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signal spi_clk_out : std_logic;

signal spi_tx_data : std_logic_vector(7 downto 0);
signal spi_rx_data : std_logic_vector(7 downto 0);

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signal spi_select_next : std_logic_vector(1 downto 0);
signal spi_select_reg : std_logic_vector(1 downto 0);
signal spi_slave_next : std_logic;
signal spi_slave_reg : std_logic;
signal spi_slave_reg_integer : integer;
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signal spi_speed_next : std_logic_vector(7 downto 0);
signal spi_speed_reg : std_logic_vector(7 downto 0);
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signal spi_speed_reg_integer : integer;
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signal uart_data_out : std_logic_vector(15 downto 0);
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signal pause_next : std_logic_vector(31 downto 0);
signal pause_reg : std_logic_vector(31 downto 0);
signal paused_next : std_logic;
signal paused_reg : std_logic;
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signal timer_next : std_logic_vector(31 downto 0);
signal timer_reg : std_logic_vector(31 downto 0);

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signal timer2_next : std_logic_vector(31 downto 0);
signal timer2_reg : std_logic_vector(31 downto 0);
signal timer2_threshold_next : std_logic_vector(31 downto 0);
signal timer2_threshold_reg : std_logic_vector(31 downto 0);

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signal spi_dma_addr_next : std_logic_vector(15 downto 0);
signal spi_dma_addrend_next : std_logic_vector(15 downto 0);
signal spi_dma_wr : std_logic;
signal spi_dma_next : std_logic;
signal spi_dma_addr_reg : std_logic_vector(15 downto 0);
signal spi_dma_addrend_reg : std_logic_vector(15 downto 0);
signal spi_dma_reg : std_logic;
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signal spi_clk_div_integer : integer;
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signal spi_slave_integer : integer;
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subtype usb_data_type is std_logic_vector(7 downto 0);
type usb_data_array is array(0 to USB-1) of usb_data_type;
signal usb_data : usb_data_array;

signal data_out_regs : std_logic_vector(31 downto 0);
signal data_out_mux : std_logic_vector(31 downto 0);
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signal i2c0_busy_next : std_logic;
signal i2c0_busy_reg : std_logic;
signal i2c0_read_data : std_logic_vector(7 downto 0);
signal i2c0_write_next : std_logic;
signal i2c0_write_reg : std_logic;
signal i2c0_write_data_reg : std_logic_vector(15 downto 0);
signal i2c0_write_data_next : std_logic_vector(15 downto 0);
signal i2c0_error : std_logic;

signal i2c1_busy_next : std_logic;
signal i2c1_busy_reg : std_logic;
signal i2c1_read_data : std_logic_vector(7 downto 0);
signal i2c1_write_next : std_logic;
signal i2c1_write_reg : std_logic;
signal i2c1_write_data_reg : std_logic_vector(15 downto 0);
signal i2c1_write_data_next : std_logic_vector(15 downto 0);
signal i2c1_error : std_logic;

-- Create 1MHz toggle from 48MHZ USB clock
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signal tick_count_next : std_logic_vector(7 downto 0);
signal tick_count_reg : std_logic_vector(7 downto 0);
signal tick_toggle_next : std_logic;
signal tick_toggle_reg : std_logic;
signal tick_toggle_safe_reg : std_logic;
signal tick_toggle_safe_next : std_logic;
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signal tick_us : std_logic;

-- pokey style 17-bit LSFR, but faster
signal rand_out : std_logic_vector(7 downto 0);
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begin
-- register
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process(clk,reset_n)
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begin
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if (reset_n='0') then
out1_reg <= (others=>'0');
out2_reg <= (others=>'0');
out3_reg <= (others=>'0');
out4_reg <= (others=>'0');
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out5_reg <= (others=>'0');
out6_reg <= (others=>'0');
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out7_reg <= (others=>'0');
out8_reg <= (others=>'0');
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spi_slave_reg <= '1';
spi_select_reg <= (others=>'1');
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spi_speed_reg <= X"80";

pause_reg <= (others=>'0');
paused_reg <= '0';
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timer_reg <= (others=>'0');
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timer2_reg <= (others=>'0');
timer2_threshold_reg <= (others=>'0');
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tick_toggle_safe_reg <= '0';
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spi_dma_addr_reg <= (others=>'0');
spi_dma_addrend_reg <= (others=>'0');
spi_dma_reg <= '0';
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i2c0_busy_reg <= '0';
i2c0_write_reg <= '0';
i2c0_write_data_reg <= (others=>'0');
i2c1_busy_reg <= '0';
i2c1_write_reg <= '0';
i2c1_write_data_reg <= (others=>'0');
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elsif (clk'event and clk='1') then
out1_reg <= out1_next;
out2_reg <= out2_next;
out3_reg <= out3_next;
out4_reg <= out4_next;
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out5_reg <= out5_next;
out6_reg <= out6_next;
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out7_reg <= out7_next;
out8_reg <= out8_next;
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spi_slave_reg <= spi_slave_next;
spi_select_reg <= spi_select_next;
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spi_speed_reg <= spi_speed_next;

pause_reg <= pause_next;
paused_reg <= paused_next;
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timer_reg <= timer_next;
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timer2_reg <= timer2_next;
timer2_threshold_reg <= timer2_threshold_next;
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tick_toggle_safe_reg <= tick_toggle_safe_next;
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spi_dma_addr_reg <= spi_dma_addr_next;
spi_dma_addrend_reg <= spi_dma_addrend_next;
spi_dma_reg <= spi_dma_next;
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i2c0_busy_reg <= i2c0_busy_next;
i2c0_write_reg <= i2c0_write_next;
i2c0_write_data_reg <= i2c0_write_data_next;
i2c1_busy_reg <= i2c1_busy_next;
i2c1_write_reg <= i2c1_write_next;
i2c1_write_data_reg <= i2c1_write_data_next;
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end if;
end process;

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-- register (tick clk)
process(CLK_nMHz,reset_n)
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begin
if (reset_n='0') then
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tick_count_reg <= (others=>'0');
tick_toggle_reg <= '0';
elsif (CLK_nMHz'event and CLK_nMHz='1') then
tick_count_reg <= tick_count_next;
tick_toggle_reg <= tick_toggle_next;
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end if;
end process;

-- create exact 1MHz
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process(tick_count_reg, tick_toggle_reg)
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begin
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tick_count_next <= std_logic_vector(unsigned(tick_count_reg)-1);
tick_toggle_next <= tick_toggle_reg;
if (or_reduce(tick_count_reg)='0') then
tick_toggle_next <= not(tick_toggle_reg);
tick_count_next <= std_logic_vector(to_unsigned(nMHz_clock_div-1,8));
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end if;
end process;

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tick_toggle_synchronizer : entity work.synchronizer
port map (clk=>clk, raw=>tick_toggle_reg, sync=>tick_toggle_safe_next);
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process(tick_toggle_safe_reg, tick_toggle_safe_next)
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begin
tick_us <= '0';
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if (tick_toggle_safe_reg = tick_toggle_safe_next) then
tick_us <= '0';
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else
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tick_us <= '1';
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end if;
end process;

-- timer for exact us
process(timer_reg,tick_us)
begin
timer_next <= timer_reg;

if (tick_us = '1') then
timer_next <= std_logic_vector(unsigned(timer_reg)+1);
end if;
end process;

process(timer2_reg,timer2_threshold_reg,tick_us)
begin
timer2_next <= timer2_reg;

if (tick_us = '1') then
timer2_next <= std_logic_vector(unsigned(timer2_reg)+1);
end if;

if (timer2_reg >= timer2_threshold_reg) then
timer2_next <= (others=>'0');
end if;
end process;

-- random result
poly_17_19_lfsr : entity work.pokey_poly_17_9
port map(clk=>clk,reset_n=>reset_n,init=>'0',enable=>'1',select_9_17=>'0',bit_out=>open,rand_out=>rand_out);

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-- decode address
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decode_addr : entity work.complete_address_decoder
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generic map(width=>5)
port map (addr_in=>addr(4 downto 0), addr_decoded=>addr_decoded);
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decode_device : entity work.complete_address_decoder
generic map(width=>3)
port map (addr_in=>addr(10 downto 8), addr_decoded=>device_decoded);

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-- spi - for sd card access without bit banging...
-- 200KHz to start with - probably fine for 8-bit, can up it later after init
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spi_clk_div_integer <= to_integer(unsigned(spi_speed_reg));
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spi_slave_integer <= to_integer(unsigned(vectorize(spi_slave_reg)));
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spi_master1 : entity work.spi_master
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generic map(slaves=>2,d_width=>8)
port map (clock=>clk,reset_n=>reset_n,enable=>spi_enable,cpol=>'0',cpha=>'0',cont=>'0',clk_div=>spi_clk_div_integer,addr=>spi_slave_integer,
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tx_data=>spi_tx_data, miso=>spi_miso,sclk=>spi_clk_out,ss_n=>spi_chip_select,mosi=>spi_mosi,
rx_data=>spi_rx_data,busy=>spi_busy);
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-- spi-programming model:
-- reg for write/read
-- data (send/receive)
-- busy
-- speed - 0=400KHz, 1=10MHz? Start with 400KHz then atari800core...
-- chip select
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-- TODO: Use real clk freq... Not that important since only used on eclaire for now anyway.
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i2c_master0 : entity work.i2c_master
generic map(input_clk=>58_000_000, bus_clk=>400_000)
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port map (clk=>clk,reset_n=>reset_n,ena=>i2c0_write_reg,addr=>i2c0_write_data_reg(15 downto 9),rw=>i2c0_write_data_reg(8),data_wr=>i2c0_write_data_reg(7 downto 0),busy=>i2c0_busy_next,data_rd=>i2c0_read_data,ack_error=>i2c0_error,
sda_in=>i2c0_sda_in,scl_in=>i2c0_scl_in,sda_wen=>i2c0_sda_wen,scl_wen=>i2c0_scl_wen);
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i2c_master1 : entity work.i2c_master
generic map(input_clk=>58_000_000, bus_clk=>400_000)
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port map (clk=>clk,reset_n=>reset_n,ena=>i2c1_write_reg,addr=>i2c1_write_data_reg(15 downto 9),rw=>i2c1_write_data_reg(8),data_wr=>i2c1_write_data_reg(7 downto 0),busy=>i2c1_busy_next,data_rd=>i2c1_read_data,ack_error=>i2c1_error,
sda_in=>i2c1_sda_in,scl_in=>i2c1_scl_in,sda_wen=>i2c1_sda_wen,scl_wen=>i2c1_scl_wen);
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-- device decode
-- 0x000 - own regs (0)
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-- 0x100 - uart (1)
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-- 0x200 - usb1 (2)
-- 0x300 - usb2 (3)
-- 0x400 - usb3 (4)
-- 0x500 - usb4 (5)
-- 0x600 - usb5 (6)
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-- 0x700 - pll (7)
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device_wr_en <= device_decoded and (wr_en&wr_en&wr_en&wr_en&wr_en&wr_en&wr_en&wr_en);
device_rd_en <= device_decoded and (rd_en&rd_en&rd_en&rd_en&rd_en&rd_en&rd_en&rd_en);
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-- pll
PLL_WRITE <= device_wr_en(7);
PLL_DATA <= cpu_data_in;
PLL_ADDR <= addr(5 downto 0); -- already shifted
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-- simplest uart, running with pokey divisors
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-- can not easily poll frequently enough with zpu when also polling usb
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--pokey_enable/(divisor(e.g. 0x28)+6)/2 = bit rate
simple_uart_inst : entity work.sio_handler
PORT MAP
(
CLK => CLK,
ADDR => addr(4 downto 0),
CPU_DATA_IN => cpu_data_in(7 downto 0),
EN => device_rd_en(1),
WR_EN => device_wr_en(1),

RESET_N => reset_n,
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POKEY_ENABLE => POKEY_ENABLE,

SIO_DATA_IN => sio_data_in,
SIO_COMMAND => sio_command,
SIO_DATA_OUT => sio_data_out,
SIO_CLK_OUT => sio_clk_out,

-- CPU interface
DATA_OUT => uart_data_out
);
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-- USB host
USBGEN:
for I in 0 to USB-1 generate
usbcon : usbHostCyc2Wrap_usb1t11
port map
(
clk_i => clk,
rst_i => not(reset_n),
address_i => addr(7 downto 0),
data_i => cpu_data_in(7 downto 0),
data_o => usb_data(I), -- 2D array
we_i => device_wr_en(I+2),
strobe_i => device_wr_en(I+2) or device_rd_en(I+2),
ack_o => open, -- always right away - checked in sim
irq => open,
usbClk => CLK_USB,

USBWireVPin => USBWireVPin(I),
USBWireVMin => USBWireVMin(I),
USBWireVPout => USBWireVPout(I),
USBWireVMout => USBWireVMout(I),
USBWireOE_n => USBWireOE_n(I),
USBFullSpeed => open
);
end generate USBGEN;

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process(device_decoded, data_out_regs, uart_data_out, usb_data)
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begin
data_out_mux <= (others=>'0');
if (device_decoded(0) = '1') then
data_out_mux <= data_out_regs;
end if;

if (device_decoded(1) = '1') then
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data_out_mux(15 downto 0) <= uart_data_out;
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end if;

for I in 0 to USB-1 loop
if (device_decoded(I+2) = '1') then
data_out_mux(7 downto 0) <= usb_data(I);
end if;
end loop;
end process;

1 markw
-- hardware regs for ZPU
--
7 markw
-- 0-3: GENERIC INPUT (RO)
-- 4-7: GENERIC OUTPUT (R/W)
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-- 8: W:PAUSE, R:Timer (1ms)
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-- 9: SPI_DATA
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-- SPI_DATA (DONE)
-- W - write data (starts transmission)
-- R - read data (wait for complete first)
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-- 10: SPI_STATE
1 markw
-- SPI_STATE/SPI_CTRL (DONE)
-- R: 0=busy
-- W: 0=select_n, speed
7 markw
-- 11: SIO
1 markw
-- SIO
-- R: 0=CMD
7 markw
-- 12: TYPE
1 markw
-- FPGA board (DONE)
-- R(32 bits) 0=DE1
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-- 13 : SPI_DMA
-- W(15 downto 0 = addr),(31 downto 16 = endAddr)
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-- 14-15 : GENERIC OUTPUT (R/W)
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-- 16 : I2C0 (W=AADD where AA is AAAAAAAR (r=1 is read)), (R=YXDD, where DD(0xff) is data, X(0x100) is busy and Y(0x200) is error)
-- 17 : I2C1 (as above, connection 2)
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-- 18 : timer - TODO docs
-- 19 : rand - TODO docs
-- 20-21 : GENERIC OUTPUT (R/W) - TODO reorganise!
1 markw
-- Writes to registers
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process(cpu_data_in,device_wr_en,addr,addr_decoded, spi_speed_reg, spi_slave_reg, spi_select_reg, out1_reg, out2_reg, out3_reg, out4_reg, out5_reg, out6_reg, out7_reg, out8_reg, pause_reg, spi_dma_addr_reg, spi_dma_addrend_reg, spi_dma_reg, spi_busy, spi_dma_addr_next, i2c0_write_reg, i2c1_write_reg, i2c0_busy_next, i2c0_busy_reg, i2c1_busy_next, i2c1_busy_reg, i2c0_write_data_reg, i2c1_write_data_reg, timer2_threshold_reg, tick_us)
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begin
spi_speed_next <= spi_speed_reg;
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spi_slave_next <= spi_slave_reg;
spi_select_next <= spi_select_reg;
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spi_tx_data <= (others=>'0');
spi_enable <= '0';
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out1_next <= out1_reg;
out2_next <= out2_reg;
out3_next <= out3_reg;
out4_next <= out4_reg;
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out5_next <= out5_reg;
out6_next <= out6_reg;
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out7_next <= out7_reg;
out8_next <= out8_reg;
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timer2_threshold_next <= timer2_threshold_reg;

1 markw
paused_next <= '0';
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pause_next <= pause_reg;
if (not(pause_reg = X"00000000")) then
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if (tick_us='1') then
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pause_next <= std_LOGIC_VECTOR(unsigned(pause_reg)-to_unsigned(1,32));
end if;
1 markw
paused_next <= '1';
end if;
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spi_dma_addr_next <= spi_dma_addr_reg;
spi_dma_addrend_next <= spi_dma_addrend_reg;
spi_dma_wr <= '0';
spi_dma_next <= spi_dma_reg;
if (spi_dma_reg = '1') then
paused_next <= '1';

if (spi_busy = '0') then
spi_dma_wr <= '1';
147 markw
spi_dma_addr_next <= std_logic_vector(unsigned(spi_dma_addr_reg)+to_unsigned(1,16));
67 markw
spi_dma_next <= '0';

if (not(spi_dma_addr_next = spi_dma_addrend_reg)) then
spi_tx_data <= X"ff";
spi_enable <= '1';
spi_dma_next <= '1';
end if;
end if;
end if;
803 markw
-- Problem here is the interaction between busy and blocking
-- When busy immediately unblocks when it needs to wait! TODO
i2c0_write_next <= i2c0_write_reg;
i2c0_write_data_next <= i2c0_write_data_reg;
if (i2c0_write_reg = '1') then
paused_next <= '1';
if (i2c0_busy_next = '1' and i2c0_busy_reg = '0') then
paused_next <= '0';
i2c0_write_next <= '0';
end if;
end if;

i2c1_write_next <= i2c1_write_reg;
i2c1_write_data_next <= i2c1_write_data_reg;
if (i2c1_write_reg = '1') then
paused_next <= '1';
if (i2c1_busy_next = '1' and i2c1_busy_reg = '0') then
paused_next <= '0';
i2c1_write_next <= '0';
end if;
end if;

277 markw
if (device_wr_en(0) = '1') then
1 markw
if(addr_decoded(4) = '1') then
7 markw
out1_next <= cpu_data_in;
1 markw
end if;

if(addr_decoded(5) = '1') then
7 markw
out2_next <= cpu_data_in;
1 markw
end if;

if(addr_decoded(6) = '1') then
7 markw
out3_next <= cpu_data_in;
end if;

if(addr_decoded(7) = '1') then
out4_next <= cpu_data_in;
end if;

277 markw
if(addr_decoded(14) = '1') then
out5_next <= cpu_data_in;
end if;

if(addr_decoded(15) = '1') then
out6_next <= cpu_data_in;
end if;

7 markw
if(addr_decoded(8) = '1') then
pause_next <= cpu_data_in;
paused_next <= '1';
end if;

if(addr_decoded(9) = '1') then
1 markw
-- TODO, check overrun?
spi_tx_data <= cpu_data_in(7 downto 0);
spi_enable <= '1';
end if;

7 markw
if(addr_decoded(10) = '1') then
803 markw
spi_slave_next <= cpu_data_in(0);
spi_select_next <= cpu_data_in(2 downto 1);
if (cpu_data_in(3) = '1') then
1 markw
spi_speed_next <= X"80"; -- slow, for init
else
57 markw
spi_speed_next <= std_logic_vector(to_unsigned(spi_clock_div,8)); -- turbo - up to 25MHz for SD, 20MHz for MMC I believe... If 1 then clock is half input, if 2 then clock is 1/4 input etc.
1 markw
end if;
end if;
67 markw
if(addr_decoded(13) = '1') then
paused_next <= '1';
spi_dma_addr_next <= cpu_data_in(15 downto 0);
spi_dma_addrend_next <= cpu_data_in(31 downto 16);

spi_dma_next <= '1';

spi_tx_data <= X"ff";
spi_enable <= '1';
end if;
803 markw
if(addr_decoded(16) = '1') then
i2c0_write_next <= '1';
paused_next <= '1';
i2c0_write_data_next <= cpu_data_in(15 downto 0);
end if;

if(addr_decoded(17) = '1') then
i2c1_write_next <= '1';
paused_next <= '1';
i2c1_write_data_next <= cpu_data_in(15 downto 0);
end if;

if(addr_decoded(18) = '1') then --timer2 threshold
timer2_threshold_next <= cpu_data_in(31 downto 0);
end if;

952 markw
if(addr_decoded(20) = '1') then
out7_next <= cpu_data_in;
end if;

if(addr_decoded(21) = '1') then
out8_next <= cpu_data_in;
end if;


1 markw
end if;
end process;

-- Read from registers
952 markw
process(addr,addr_decoded, in1, in2, in3, in4, out1_reg, out2_reg, out3_reg, out4_reg, out5_reg, out6_reg, out7_reg, out8_reg, SIO_COMMAND, spi_rx_data, spi_busy, timer_reg, timer2_reg, i2c0_busy_reg, i2c0_read_data, i2c1_busy_reg, i2c1_read_data, i2c0_error, i2c1_error, rand_out)
1 markw
begin
277 markw
data_out_regs <= (others=>'0');
1 markw
277 markw
if (addr_decoded(0) = '1') then
data_out_regs <= in1;
end if;

if (addr_decoded(1) = '1') then
data_out_regs <= in2;
end if;

if (addr_decoded(2) = '1') then
data_out_regs <= in3;
end if;

if (addr_decoded(3) = '1') then
data_out_regs <= in4;
end if;
7 markw
277 markw
if (addr_decoded(4) = '1') then
data_out_regs <= out1_reg;
end if;

if (addr_decoded(5) = '1') then
data_out_regs <= out2_reg;
end if;

if (addr_decoded(6) = '1') then
data_out_regs <= out3_reg;
end if;

if (addr_decoded(7) = '1') then
data_out_regs <= out4_reg;
end if;
1 markw
277 markw
if (addr_decoded(14) = '1') then
data_out_regs <= out5_reg;
end if;
1 markw
277 markw
if (addr_decoded(15) = '1') then
data_out_regs <= out6_reg;
end if;
1 markw
952 markw
if(addr_decoded(20) = '1') then
data_out_regs <= out7_reg;
end if;

if(addr_decoded(21) = '1') then
data_out_regs <= out8_reg;
end if;

277 markw
if (addr_decoded(8) = '1') then
data_out_regs <= timer_reg;
1 markw
end if;
277 markw
if (addr_decoded(9) = '1') then
data_out_regs(7 downto 0) <= spi_rx_data;
end if;

if (addr_decoded(10) = '1') then
data_out_regs(0) <= spi_busy;
end if;

if(addr_decoded(11) = '1') then
data_out_regs(0) <= SIO_COMMAND;
end if;

if (addr_decoded(12) = '1') then
data_out_regs <= std_logic_vector(to_unsigned(platform,32));
end if;
803 markw
if (addr_decoded(16) = '1') then
data_out_regs(9) <= i2c0_error;
data_out_regs(8) <= i2c0_busy_reg;
data_out_regs(7 downto 0) <= i2c0_read_data;
end if;

if (addr_decoded(17) = '1') then
data_out_regs(9) <= i2c1_error;
data_out_regs(8) <= i2c1_busy_reg;
data_out_regs(7 downto 0) <= i2c1_read_data;
end if;


if(addr_decoded(18) = '1') then -- timer2 value
data_out_regs <= timer2_reg;
end if;

if(addr_decoded(19) = '1') then -- rand
data_out_regs(7 downto 0) <= rand_out;
end if;
1 markw
end process;

-- outputs
PAUSE_ZPU <= paused_reg;
7 markw
out1 <= out1_reg;
out2 <= out2_reg;
out3 <= out3_reg;
out4 <= out4_reg;
277 markw
out5 <= out5_reg;
out6 <= out6_reg;
952 markw
out7 <= out7_reg;
out8 <= out8_reg;
1 markw
803 markw
--SDCARD_CLK <= spi_clk_out;
--SDCARD_CMD <= spi_mosi;
--spi_miso <= SDCARD_DAT; -- INPUT!! XXX
--SDCARD_DAT3 <= spi_chip_select(0);
--FLASH_SELECT <= spi_chip_select(1);
67 markw
803 markw
SPI_CLK <= spi_clk_out;
SPI_DO <= spi_mosi;
spi_miso <= SPI_DI; -- INPUT!! XXX
SPI_SELECT0 <= spi_select_reg(0);
SPI_SELECT1 <= spi_select_reg(1);

277 markw
data_out <= data_out_mux;

67 markw
sd_addr <= spi_dma_addr_reg;
sd_data <= spi_rx_data;
sd_write <= spi_dma_wr;
1 markw
end vhdl;