frequ.bsf

程序用VHDL实现： 利用一秒定时测量频率 并且显示

/*
WARNING: Do NOT edit the input and output ports in this file in a text
editor if you plan to continue editing the block that represents it in
the Block Editor! File corruption is VERY likely to occur.
*/
/*
Copyright (C) 1991-2004 Altera Corporation
Any  megafunction  design,  and related netlist (encrypted  or  decrypted),
support information,  device programming or simulation file,  and any other
associated  documentation or information  provided by  Altera  or a partner
under  Altera's   Megafunction   Partnership   Program  may  be  used  only
to program  PLD  devices (but not masked  PLD  devices) from  Altera.   Any
other  use  of such  megafunction  design,  netlist,  support  information,
device programming or simulation file,  or any other  related documentation
or information  is prohibited  for  any  other purpose,  including, but not
limited to  modification,  reverse engineering,  de-compiling, or use  with
any other  silicon devices,  unless such use is  explicitly  licensed under
a separate agreement with  Altera  or a megafunction partner.  Title to the
intellectual property,  including patents,  copyrights,  trademarks,  trade
secrets,  or maskworks,  embodied in any such megafunction design, netlist,
support  information,  device programming or simulation file,  or any other
related documentation or information provided by  Altera  or a megafunction
partner, remains with Altera, the megafunction partner, or their respective
licensors. No other licenses, including any licenses needed under any third
party's intellectual property, are provided herein.
*/
(header "symbol" (version "1.1"))
(symbol
	(rect 16 16 144 144)
	(text "frequ" (rect 5 0 35 14)(font "Arial" (font_size 8)))
	(text "inst" (rect 8 112 25 124)(font "Arial" ))
	(port
		(pt 0 32)
		(input)
		(text "clk1" (rect 0 0 22 14)(font "Arial" (font_size 8)))
		(text "clk1" (rect 21 27 43 41)(font "Arial" (font_size 8)))
		(line (pt 0 32)(pt 16 32)(line_width 1))
	)
	(port
		(pt 0 48)
		(input)
		(text "start" (rect 0 0 25 14)(font "Arial" (font_size 8)))
		(text "start" (rect 21 43 46 57)(font "Arial" (font_size 8)))
		(line (pt 0 48)(pt 16 48)(line_width 1))
	)
	(port
		(pt 0 64)
		(input)
		(text "clk" (rect 0 0 15 14)(font "Arial" (font_size 8)))
		(text "clk" (rect 21 59 36 73)(font "Arial" (font_size 8)))
		(line (pt 0 64)(pt 16 64)(line_width 1))
	)
	(port
		(pt 0 80)
		(input)
		(text "clk1m" (rect 0 0 31 14)(font "Arial" (font_size 8)))
		(text "clk1m" (rect 21 75 52 89)(font "Arial" (font_size 8)))
		(line (pt 0 80)(pt 16 80)(line_width 1))
	)
	(port
		(pt 128 32)
		(output)
		(text "led[6..0]" (rect 0 0 44 14)(font "Arial" (font_size 8)))
		(text "led[6..0]" (rect 63 27 107 41)(font "Arial" (font_size 8)))
		(line (pt 128 32)(pt 112 32)(line_width 3))
	)
	(port
		(pt 128 48)
		(output)
		(text "ledpt" (rect 0 0 27 14)(font "Arial" (font_size 8)))
		(text "ledpt" (rect 80 43 107 57)(font "Arial" (font_size 8)))
		(line (pt 128 48)(pt 112 48)(line_width 1))
	)
	(port
		(pt 128 64)
		(output)
		(text "sa" (rect 0 0 14 14)(font "Arial" (font_size 8)))
		(text "sa" (rect 93 59 107 73)(font "Arial" (font_size 8)))
		(line (pt 128 64)(pt 112 64)(line_width 1))
	)
	(port
		(pt 128 80)
		(output)
		(text "sb" (rect 0 0 14 14)(font "Arial" (font_size 8)))
		(text "sb" (rect 93 75 107 89)(font "Arial" (font_size 8)))
		(line (pt 128 80)(pt 112 80)(line_width 1))
	)
	(port
		(pt 128 96)
		(output)
		(text "sc" (rect 0 0 14 14)(font "Arial" (font_size 8)))
		(text "sc" (rect 93 91 107 105)(font "Arial" (font_size 8)))
		(line (pt 128 96)(pt 112 96)(line_width 1))
	)
	(drawing
		(rectangle (rect 16 16 112 112)(line_width 1))
	)
)