做底层软件都需要哪些知识啊?

本人想做底层软件开发,可并不知道要具备哪些知识?<br />底层软件是不是就是那些驱动程序啊?<br />

If&nbsp;you&nbsp;want&nbsp;to&nbsp;do&nbsp;what&nbsp;you&nbsp;said,you&nbsp;should&nbsp;workhard.I&nbsp;take&nbsp;USB&nbsp;device&nbsp;develop&nbsp;as&nbsp;an&nbsp;example.<br />To&nbsp;develop&nbsp;an&nbsp;USB&nbsp;device,you&nbsp;should&nbsp;know:<br />1.How&nbsp;to&nbsp;design&nbsp;the&nbsp;hardware&nbsp;topography.It&nbsp;requst&nbsp;you&nbsp;good&nbsp;at&nbsp;read&nbsp;English&nbsp;articles.Most&nbsp;IC&nbsp;articles&nbsp;not&nbsp;wrote&nbsp;by&nbsp;Chinese&nbsp;but&nbsp;English.<br />2.How&nbsp;to&nbsp;write&nbsp;firmware.Usally,We&nbsp;use&nbsp;MCU&nbsp;with&nbsp;USBSIE.It&nbsp;requst&nbsp;you&nbsp;master&nbsp;Instructions&nbsp;of&nbsp;the&nbsp;MCU.<br />3.The&nbsp;most&nbsp;hard&nbsp;work&nbsp;may&nbsp;be&nbsp;write&nbsp;a&nbsp;good&nbsp;driver.It&nbsp;requst&nbsp;lots&nbsp;of&nbsp;knowledge.<br />4.GUI&nbsp;program.