请AVR电子工程师帮帮忙
ISP Mode Error
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A problem occured when executing the command. See the command output for more info.
Tip: Check that the ISP programming frequency specified on the 'Board' page is well
below 1/4 of the clock frequency of the device. Extra precaution should be made when
using the CKDIV fuse and/or Clock Prescaler Register (CLKPR) on parts supporting
this. If this does not help, check your connections.
See the troubleshooting section in the help system for more information on what may
have caused the problems.
我不知道改了什么程序就下不进去，以为锁死了芯片，结果换了芯片MEGA48还是不行，
board选项卡上的ISP速度我全部试过了，都不行，会不会是我不小心关闭了内部振荡器，又没有使能外部的，
