[Uart]

- uart_wb instantiates uart
- merged uart_tx, uart_rx into uart
- added uart implementations for Xilinx (kcuart) and Altera (JTAG)

git-svn-id: http://moon:8086/svn/vhdl/trunk@1239 cc03376c-175c-47c8-b038-4cd826a8556b

lib/uart/uart_tx.vhd

@@ -1,153 +0,0 @@
--- UART Transmitter with integral 16 byte FIFO buffer
---
--- 8 bit, no parity, 1 stop bit
---
--- Version : 1.00
--- Version Date : 14th October 2002
---
--- Start of design entry : 14th October 2002
---
--- Ken Chapman
--- Xilinx Ltd
--- Benchmark House
--- 203 Brooklands Road
--- Weybridge
--- Surrey KT13 ORH
--- United Kingdom
---
--- chapman@xilinx.com
---
-------------------------------------------------------------------------------------
---
--- NOTICE:
---
--- Copyright Xilinx, Inc. 2002.   This code may be contain portions patented by other 
--- third parties.  By providing this core as one possible implementation of a standard,
--- Xilinx is making no representation that the provided implementation of this standard 
--- is free from any claims of infringement by any third party.  Xilinx expressly 
--- disclaims any warranty with respect to the adequacy of the implementation, including 
--- but not limited to any warranty or representation that the implementation is free 
--- from claims of any third party.  Futhermore, Xilinx is providing this core as a 
--- courtesy to you and suggests that you contact all third parties to obtain the 
--- necessary rights to use this implementation.
---
-------------------------------------------------------------------------------------
---
--- Library declarations
---
--- The Unisim Library is used to define Xilinx primitives. It is also used during
--- simulation. The source can be viewed at %XILINX%\vhdl\src\unisims\unisim_VCOMP.vhd
---
-library IEEE;
-use IEEE.STD_LOGIC_1164.ALL;
-use IEEE.STD_LOGIC_ARITH.ALL;
-use IEEE.STD_LOGIC_UNSIGNED.ALL;
-library unisim;
-use unisim.vcomponents.all;
---
-------------------------------------------------------------------------------------
---
--- Main Entity for UART_TX
---
-entity uart_tx is
-    Port (            data_in : in std_logic_vector(7 downto 0);
-                 write_buffer : in std_logic;
-                 reset_buffer : in std_logic;
-                 en_16_x_baud : in std_logic;
-                   serial_out : out std_logic;
-                  buffer_full : out std_logic;
-             buffer_half_full : out std_logic;
-             tx_complete	  : out std_logic;
-             tx_empty		  : out std_logic;
-                          clk : in std_logic);
-    end uart_tx;
---
-------------------------------------------------------------------------------------
---
--- Start of Main Architecture for UART_TX
---	 
-architecture macro_level_definition of uart_tx is
---
-------------------------------------------------------------------------------------
---
--- Components used in UART_TX and defined in subsequent entities.
---	
-------------------------------------------------------------------------------------
---
--- Constant (K) Compact UART Transmitter
---
-component kcuart_tx 
-    Port (        data_in : in std_logic_vector(7 downto 0);
-           send_character : in std_logic;
-             en_16_x_baud : in std_logic;
-               serial_out : out std_logic;
-              Tx_complete : out std_logic;
-                      clk : in std_logic);
-    end component;
---
--- 'Bucket Brigade' FIFO 
---
-component bbfifo_16x8 
-    Port (       data_in : in std_logic_vector(7 downto 0);
-                data_out : out std_logic_vector(7 downto 0);
-                   reset : in std_logic;               
-                   write : in std_logic; 
-                    read : in std_logic;
-                    full : out std_logic;
-               half_full : out std_logic;
-            data_present : out std_logic;
-                     clk : in std_logic);
-    end component;
---
-------------------------------------------------------------------------------------
---
--- Signals used in UART_TX
---
-------------------------------------------------------------------------------------
---
-signal fifo_data_out      : std_logic_vector(7 downto 0);
-signal fifo_data_present  : std_logic;
-signal fifo_read          : std_logic;
---
-------------------------------------------------------------------------------------
---
--- Start of UART_TX circuit description
---
-------------------------------------------------------------------------------------
---	
-begin
-
-  tx_complete	<= fifo_read;
-  tx_empty		<= not fifo_data_present;
-  
-  -- 8 to 1 multiplexer to convert parallel data to serial
-
-  kcuart: kcuart_tx
-  port map (        data_in => fifo_data_out,
-             send_character => fifo_data_present,
-               en_16_x_baud => en_16_x_baud,
-                 serial_out => serial_out,
-                Tx_complete => fifo_read,
-                        clk => clk);
-
-
-  buf: bbfifo_16x8 
-  port map (       data_in => data_in,
-                  data_out => fifo_data_out,
-                     reset => reset_buffer,              
-                     write => write_buffer,
-                      read => fifo_read,
-                      full => buffer_full,
-                 half_full => buffer_half_full,
-              data_present => fifo_data_present,
-                       clk => clk);
-
-end macro_level_definition;
-
-------------------------------------------------------------------------------------
---
--- END OF FILE UART_TX.VHD
---
-------------------------------------------------------------------------------------
-
-