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--
--
-- !!! ======================== [ WARNING ] ======================== !!!
--
-- QUICK-AND-DIRTY TESTBENCH ... SCHEDULED FOR CLEAN UP
--
-- !!! ======================== [ WARNING ] ======================== !!!
--
--
-- Copyright (c) 2013 Nuand LLC
--
-- Permission is hereby granted, free of charge, to any person obtaining a copy
-- of this software and associated documentation files (the "Software"), to deal
-- in the Software without restriction, including without limitation the rights
-- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-- copies of the Software, and to permit persons to whom the Software is
-- furnished to do so, subject to the following conditions:
--
-- The above copyright notice and this permission notice shall be included in
-- all copies or substantial portions of the Software.
--
-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-- THE SOFTWARE.
library ieee ;
use ieee.std_logic_1164.all ;
use ieee.numeric_std.all ;
use ieee.math_real.all ;
use ieee.math_complex.all ;
entity lms6002d_model is
port (
-- LMS RX Interface
rx_clock : in std_logic ;
rx_clock_out : buffer std_logic ;
rx_data : buffer signed(11 downto 0) ;
rx_enable : in std_logic ;
rx_iq_select : buffer std_logic ;
-- LMS TX Interface
tx_clock : in std_logic ;
tx_data : in signed(11 downto 0) ;
tx_enable : in std_logic ;
tx_iq_select : in std_logic ;
-- LMS SPI Interface
sclk : in std_logic ;
sen : in std_logic ;
sdio : in std_logic ;
sdo : buffer std_logic ;
-- LMS Control Interface
pll_out : buffer std_logic ;
resetx : in std_logic
) ;
end entity ; -- lms6002d_model
architecture arch of lms6002d_model is
constant SPI_CMD_WIDTH : positive := 1;
constant SPI_ADDR_WIDTH : positive := 7;
constant SPI_DATA_WIDTH : positive := 8;
constant SPI_MSG_WIDTH : positive := 16; -- total number of bits in a SPI message
constant SPI_NUM_REGS : positive := 128; -- number of SPI registers
type spi_registers_t is array( 0 to SPI_NUM_REGS-1 ) of std_logic_vector( SPI_DATA_WIDTH-1 downto 0 );
signal spi_registers : spi_registers_t := (others => (others => '1') );
begin
pll_out <= '0' ;
-- Write transmit samples to a file or drop them on the floor
-- Read receive samples from a file or predetermined tone
rx_clock_out <= rx_clock ;
drive_rx_data : process( resetx, rx_clock )
begin
if( resetx = '0' ) then
rx_data <= (others =>'0') ;
rx_iq_select <= '0' ;
elsif( rising_edge(rx_clock) ) then
if( rx_enable = '1' ) then
rx_data <= rx_data + 1 ;
rx_iq_select <= not rx_iq_select ;
else
rx_data <= (others =>'0') ;
rx_iq_select <= '0' ;
end if ;
end if ;
end process ;
-- Keep track of the SPI register set
spi_reg_proc : process( sclk )
variable ptr : natural range 0 to SPI_MSG_WIDTH-1 := 0;
variable addr : std_logic_vector( SPI_ADDR_WIDTH-1 downto 0 ) := (others => '0');
variable data : std_logic_vector( SPI_DATA_WIDTH-1 downto 0 ) := (others => '0');
-- Not going to bother making this generic
variable cmd : std_logic := '0';
constant RD_CMD : std_logic := '0';
constant WR_CMD : std_logic := '1';
-- Trying this method out as a thought experiment since SPI is isolated.
-- The main register array is a signal because we may want to use it elsewhere.
type spi_state_t is ( RX_CMD, RX_ADDR, RX_DATA, TX_DATA );
variable spi_state : spi_state_t := RX_CMD;
begin
sdo <= '0'; -- default
if( rising_edge(sclk) ) then
if( sen = '0' ) then
case( spi_state ) is
when RX_CMD =>
cmd := sdio;
ptr := ptr + 1;
if( ptr = SPI_CMD_WIDTH ) then
ptr := 0;
spi_state := RX_ADDR;
end if;
when RX_ADDR =>
addr := addr(addr'left-1 downto 0) & sdio;
ptr := ptr + 1;
if( ptr = SPI_ADDR_WIDTH ) then
if( cmd = RD_CMD ) then
data := spi_registers(to_integer(unsigned(addr)));
ptr := 0;
spi_state := TX_DATA;
elsif( cmd = WR_CMD ) then
ptr := 0;
spi_state := RX_DATA;
else
report "Unknown command value" severity failure;
end if;
end if;
when RX_DATA =>
data := data(data'left-1 downto 0) & sdio;
ptr := ptr + 1;
if( ptr = SPI_DATA_WIDTH ) then
spi_registers(to_integer(unsigned(addr))) <= data;
ptr := 0;
spi_state := RX_CMD;
end if;
when TX_DATA =>
sdo <= data(data'left);
data := data(data'left-1 downto 0) & "0";
ptr := ptr + 1;
if( ptr = SPI_DATA_WIDTH ) then
ptr := 0;
spi_state := RX_CMD;
end if;
end case;
else
ptr := 0;
data := (others => '0');
addr := (others => '0');
cmd := '0';
spi_state := RX_CMD;
end if;
end if;
end process;
end architecture ; -- arch
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