clock.pnx

vhdl经典源代码——时钟设计

<?xml version='1.0' encoding='utf-8' ?>
<!DOCTYPE ibis [
<!ELEMENT ibis (part, pin+)>
<!ELEMENT part EMPTY>
<!ELEMENT pin EMPTY>
<!ATTLIST part
  arch   CDATA #REQUIRED
  device CDATA #REQUIRED
  spg    CDATA #REQUIRED
  pkg    CDATA #REQUIRED>
<!ATTLIST pin
  nm     CDATA #REQUIRED
  no     CDATA #REQUIRED
  iostd  (TTL|LVTTL|LVCMOS2|NA) "NA"
  sr     (SLOW|FAST|slow|fast) "SLOW"
  dir    (BIDIR|bidir|INPUT|input|OUTPUT|output) "BIDIR">
]>
<ibis><part pkg="TQ144" spg="-10" arch="xc9500xl" device="XC95144XL"/><pin nm="rst" no="71" dir="input"/><pin nm="clk" no="128" dir="input"/><pin nm="en&lt;0&gt;" no="134" sr="fast" dir="output"/><pin nm="en&lt;1&gt;" no="133" sr="fast" dir="output"/><pin nm="en&lt;2&gt;" no="125" sr="fast" dir="output"/><pin nm="en&lt;3&gt;" no="124" sr="fast" dir="output"/><pin nm="en&lt;4&gt;" no="120" sr="fast" dir="output"/><pin nm="en&lt;5&gt;" no="126" sr="fast" dir="output"/><pin nm="en&lt;6&gt;" no="131" sr="fast" dir="output"/><pin nm="en&lt;7&gt;" no="132" sr="fast" dir="output"/><pin nm="dataout&lt;2&gt;" no="116" sr="fast" dir="output"/><pin nm="dataout&lt;3&gt;" no="115" sr="fast" dir="output"/><pin nm="dataout&lt;4&gt;" no="113" sr="fast" dir="output"/><pin nm="dataout&lt;5&gt;" no="111" sr="fast" dir="output"/><pin nm="dataout&lt;6&gt;" no="107" sr="fast" dir="output"/><pin nm="dataout&lt;7&gt;" no="106" sr="fast" dir="output"/><pin nm="dataout&lt;1&gt;" no="118" sr="fast" dir="output"/><pin nm="dataout&lt;0&gt;" no="119" sr="fast" dir="output"/></ibis>