利用定时器中断制作方波发生器，通过LED灯的暗亮时间来测量其周期-Use timer interrupt the production of square-wave generator, through the dark bright LED lights to measure the cycle time
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.002823s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.119199s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.002642s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.003335s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.002806s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.006449s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.002510s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003487s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.016246s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.002572s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 271861 [ RunTime:0.001093s ]
