TM4C129XNCZAD如何配置JTAG口为普通IO用

如题，请问如何配置JTAG口为普通IO用，使用GPIOPinTypeGPIOOutput配置TDO，发现没有作用，TDO一直为高

xyz549040622：

JTAG口默认为下载口，需要解锁才可以配置为普通IO的。但是最好不要这么做，配置为普通IO的话，就无法下载仿真了，除非你使能串口或者usb下载。

allyzc li：

回复 xyz549040622:

已配置成功，下载时直接接JLINK也能下载

void GPIOorJTAG(uint8_t gpio_or_jtag){if(gpio_or_jtag == 0) //配置为JTAG{// Change PC0-3 into hardware (i.e. JTAG) pins.First open the// lock and select the bits we want to modify in the GPIO commit// register.//HWREG(GPIO_PORTC_BASE + GPIO_O_LOCK) = GPIO_LOCK_KEY;HWREG(GPIO_PORTC_BASE + GPIO_O_CR) = 0x0F;//// Now modify the configuration of the pins that we unlocked.//HWREG(GPIO_PORTC_BASE + GPIO_O_AFSEL) |= 0x0F;//// Finally, clear the commit register and the lock to prevent// the pin configuration from being changed accidentally later.// Note that the lock is closed whenever we write to the GPIO_O_CR// register so we need to reopen it here.//HWREG(GPIO_PORTC_BASE + GPIO_O_LOCK) = GPIO_LOCK_KEY;HWREG(GPIO_PORTC_BASE + GPIO_O_CR) = 0x00;HWREG(GPIO_PORTC_BASE + GPIO_O_LOCK) = 0;}else //配置为GPIO{//// Change PC0-3 into GPIO inputs. First open the lock and select// the bits we want to modify in the GPIO commit register.//HWREG(GPIO_PORTC_BASE + GPIO_O_LOCK) = GPIO_LOCK_KEY;HWREG(GPIO_PORTC_BASE + GPIO_O_CR) = 0x0F;//// Now modifiy the configuration of the pins that we unlocked.// Note that the DriverLib GPIO functions may need to access// registers protected by the lock mechanism so these calls should// be made while the lock is open here.//HWREG(GPIO_PORTC_BASE + GPIO_O_AFSEL) &= 0xf0;//这里配置GPIOGPIOPinTypeGPIOInput(GPIO_PORTC_BASE, GPIO_PIN_2);GPIOPinTypeGPIOOutput(GPIO_PORTC_BASE, GPIO_PIN_3);GPIOPadConfigSet(GPIO_PORTC_BASE, GPIO_PIN_3, GPIO_STRENGTH_12MA, GPIO_PIN_TYPE_STD);//// Finally, clear the commit register and the lock to prevent// the pin configuration from being changed accidentally later.// Note that the lock is closed whenever we write to the GPIO_O_CR// register so we need to reopen it here.//HWREG(GPIO_PORTC_BASE + GPIO_O_LOCK) = GPIO_LOCK_KEY;HWREG(GPIO_PORTC_BASE + GPIO_O_CR) = 0x00;HWREG(GPIO_PORTC_BASE + GPIO_O_LOCK) = 0;}}

xyz549040622：

回复 allyzc li:

当配置为普通io使用的时候，如何才能下载呢？理论上是不可以的吧，你是如何实现的。

Seven Han：

回复 xyz549040622:

当配置为普通io使用的时候，如何才能下载呢？理论上是不可以的吧，你是如何实现的。

xyz549040622：

回复 Seven Han:

我试试这段代码。