PORT PULL-UP REGISTER(GPBUP-GPJUP)
The port pull-up register controls the pull-up resister enable/disable of each port group. When the corresponding
bit is 0, the pull-up resister of the pin is enabled. When 1, the pull-up resister is disabled.
设置内部上拉!
PORT PULL-UP REGISTER(GPBUP-GPJUP)
The port pull-up register controls the pull-up resister enable/disable of each port group. When the correspondingbit is 0, the pull-up resister of the pin is enabled. When 1, the pull-up resister is disabled.
If the port pull-up register is enabled then the pull-up resisters work without pin’s functional setting(input, output,DATAn, EINTn and etc)
在2440手册里找的,意思就是用来设置是否要使用上拉电阻