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Mix Module
The VHDL code used to synthesize the logic for the mix module address
decode GAL is shown below:
-----------------------------------------------------------------------------
-- DACS : Distributed Audio Control System
--
-- Copyright (C) 1997 Stephen Scott Richardson
-----------------------------------------------------------------------------
-- File: mix-1.vhd
-- Date: 03.13.97
-- Target: Atmel ATF16V8B
-----------------------------------------------------------------------------
-- Mix board pbus address decoding GAL
-- first mix board
--
-- pbus addx function dir (from uC)
-- ==================================================
-- 0x10 latch ena out
-----------------------------------------------------------------------------
ENTITY mix_decode IS
PORT (
addx_in : IN bit_vector (6 DOWNTO 0);
nlatch_in : IN bit;
nread_write_in : IN bit;
data_ena_out : OUT bit;
nsense_out : OUT bit
);
-- force part and pinout
ATTRIBUTE part_name of mix_decode:entity is "C16V8";
ATTRIBUTE pin_numbers of mix_decode:entity is
"nread_write_in:1 nlatch_in:2 addx_in(0):3 addx_in(1):4
addx_in(2):5 addx_in(3):6 addx_in(4):7 addx_in(5):8
addx_in(6):9 nsense_out:12 data_ena_out:13";
END mix_decode;
ARCHITECTURE behavior OF mix_decode IS
BEGIN
PROCESS (nlatch_in, addx_in, nread_write_in)
BEGIN
IF nlatch_in = '0' AND nread_write_in = '1'
AND addx_in = "0010000" THEN
-- pbus 0x10
nsense_out <= '0'; -- pbus nsense ACTIVE
data_ena_out <= '1'; -- data latch ena ACTIVE
ELSE
-- not active
nsense_out <= '1'; -- pbus nsense ACTIVE
data_ena_out <= '0'; -- data latch ena INACTIVE
END IF;
END PROCESS;
END behavior;
The pinout for the mixer module decode GAL is shown below:
C16V8A
_______________
nread_write_in =| 1| |20|* not used
nlatch_in =| 2| |19|* not used
addx_in_0 =| 3| |18|* not used
addx_in_1 =| 4| |17|* not used
addx_in_2 =| 5| |16|* not used
addx_in_3 =| 6| |15|* not used
addx_in_4 =| 7| |14|* not used
addx_in_5 =| 8| |13|= data_ena_out
addx_in_6 =| 9| |12|= nsense_out
not used *|10| |11|* not used
_______________
Steve Richardson
2000-07-06
|