read_return_pre_set.vhd

rs422协议的通讯程序.做一些简单改动即可以移植到各种环境。

library ieee;

use ieee.std_logic_1164.all;

entity read_return_pre_set is port(
		rst					: in std_logic;
----------来自预置控制器的参数		
		cm_code				: out std_logic_vector(3 downto 0);
		mode				: out std_logic;--和方式选择
		set_key				: out std_logic;	
		sd_code				: out std_logic_vector(3 downto 0);--包括sd和设定开关
--------CPU要写的数据------------------------------		
		cm_err_code			: in std_logic_vector(3 downto 0);--cm出错编码
		sd_err_code			: in std_logic_vector(3 downto 0);--sd出错编码
--------回送方式标志位--------------
--0=正常数据回送，1=错误码回送
		TC					: in std_logic;	
--------状态灯-----
		y7b_err_led			: in std_logic;
		y7b_put_led			: in std_logic;
		y7b_ready_led		: in std_logic;
		p1mhz				: in std_logic;
		set_rx				: in std_logic;
		set_tx				: out std_logic;
		-------使预置控制器的mode led闪动------------
		flash_mode_led		: in std_logic;
		rst_flash_mode_led	: out std_logic;--来自预置控制器串行16位的第rx(9)位
		flash_ready_led		: in std_logic;--使准备灯，cm,sd闪烁。
		--使CM,SD的回送值从cm_err_code,sd_err_code取出
		XT					: IN STD_LOGIC;
		XT_MODE				: IN STD_lOGIC--用于CPU回送
		
		
);
end entity;

architecture read_return of read_return_pre_set is

component rx16 is port(
		rst				: in std_logic;
		p1mhz			: in std_logic;
		rx				: in std_logic;
		data_out		: out std_logic_vector(15 downto 0);
		rx_tag			: out std_logic;
		rst_rx			: in std_logic
);
end component;

component tx16 is port(
		rst			: in std_logic;
		p1mhz		: in std_logic;
		data_in 	: in std_logic_vector(15 downto 0);
		tx			: out std_logic;
		start_tx	: in std_logic;
		on_tx 		: out std_logic 		
);
end component;

signal t_rx_temp : std_logic_vector(15 downto 0);
signal t_tx_temp : std_logic_vector(15 downto 0);
signal t_sd_code : std_logic_vector(2 downto 0);
signal t_rx_tag : std_logic;
signal t_beg_rst_rx , t_end_rst_rx : std_logic;
signal rx_cnt : integer range 0 to 60;
signal temp_sd : std_logic_vector(2 downto 0);
signal t_rst_rx : std_logic;
signal t_start_tx : std_logic;
signal t_on_tx : std_logic;
signal t_lock_pre_set_key : std_logic;


begin

----------------以下是从串口得到数据，发送到cm_code_out和sd_code_out
--接着发送数据到串口sd_code_in,cm_code_in

u_rx : rx16 port map(
		rst				=> rst,--: in std_logic;
		p1mhz			=> p1mhz,--: in std_logic;
		rx				=> set_rx,--: in std_logic;
		data_out		=> t_rx_temp,--: out std_logic_vector(15 downto 0);
		rx_tag			=> t_rx_tag,--: out std_logic;
		rst_rx			=> t_rst_rx--: in std_logic
);

setup_rst_rx : process(rst,t_end_rst_rx,t_rx_tag)
begin
	if rst = '0' or t_end_rst_rx = '1' then
		t_beg_rst_rx <= '0' ;
	else 
		if rising_edge (t_rx_tag) then	
			t_beg_rst_rx <= '1' ;
		end if;
	end if;		
end process;

process(rst,t_rx_tag,p1mhz,t_beg_rst_rx)
begin
	if rst='0' or t_beg_rst_rx = '0' then
		t_end_rst_rx <= '0';
		t_rst_rx <= '1';
		rx_cnt <= 0;
		t_start_tx <= '0';
	else
		if rising_edge(p1mhz) then	
			if t_beg_rst_rx = '1' then
				if rx_cnt < 5 then
					rx_cnt <= rx_cnt + 1;
					t_rst_rx <= '1';
				elsif rx_cnt < 7 then
					rx_cnt <= rx_cnt + 1;
					t_rst_rx <= '0';
				elsif rx_cnt < 12 then
					t_rst_rx <= '1';
					rx_cnt <= rx_cnt + 1;
				elsif rx_cnt < 27 then
					rx_cnt <= rx_cnt + 1;
				elsif rx_cnt < 37 then
					t_start_tx <= '1';
					rx_cnt <= rx_cnt + 1;
				elsif rx_cnt < 43 then
					rx_cnt <= rx_cnt + 1;
				elsif rx_cnt = 43 then				
					t_start_tx <= '0';		
					rx_cnt <= 0;
					t_end_rst_rx <= '1';
				end if;	
			end if;
		end if;		
	end if;	
end process;


cm_code <= t_rx_temp(15 downto 12);
-----------送到io component 使flash_mode_led复位----------------------
rst_flash_mode_led <= t_rx_temp(9);
mode <= t_rx_temp(8);
set_key <= t_rx_temp(7);
sd_code <= t_rx_temp(3 downto 0) ;



-----------以下是发送数据到串口--2007-11-12,9:02
t_tx_temp(15 downto 12) <= cm_err_code when tc='1' OR XT='1' else t_rx_temp(15 downto 12);
t_tx_temp(11) <= TC;
t_tx_temp(10) <= flash_ready_led;--使准备，cm,sd闪烁
-------使预置控制器的mode led闪动------------
t_tx_temp(9) <= flash_mode_led; 
t_tx_temp(8) <= XT_MODE WHEN XT='1' ELSE t_rx_temp(8);--cir_snk 开关值回送 
t_tx_temp(7) <= '0';
t_tx_temp(6) <= y7b_err_led;--故障灯
t_tx_temp(5) <= y7b_ready_led;--准备灯
t_tx_temp(4) <= y7b_put_led;	--，投放灯		
t_tx_temp(3 downto 0) <= sd_err_code when tc='1' OR XT='1' else t_rx_temp(3 downto 0) ;

u_tx : tx16 port map(
		rst			=> rst,--: in std_logic;
		p1mhz		=> p1mhz,--: in std_logic;
		data_in 	=> t_tx_temp ,--: in std_logic_vector(15 downto 0);
		tx			=> set_tx,--: out std_logic;
		start_tx	=> t_start_tx,--: in std_logic;
		on_tx 		=> t_on_tx--: out std_logic 		
);
end architecture ;