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TM4C123GH6PM - Unable to connect to the target device

Other Parts Discussed in Thread: EK-TM4C123GXL

Hi guys, I'm using CCS Version: 5.5.0.00077 , the CCS cannot connect to my TM4C, please help!


Here is the code I used to test device :

#include <stdint.h>
#include <stdbool.h>
#include "inc/hw_types.h"
#include "inc/hw_memmap.h"
#include "driverlib/sysctl.h"
#include "driverlib/gpio.h"

int main(void) {
	uint32_t value = 0;
	uint8_t state = 0;
	SysCtlClockSet(
			SYSCTL_SYSDIV_2_5 | SYSCTL_USE_PLL | SYSCTL_XTAL_16MHZ
					| SYSCTL_OSC_MAIN);
	SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
	GPIOPinTypeGPIOOutput(GPIO_PORTB_BASE, GPIO_PIN_2);
	GPIOPinTypeGPIOInput(GPIO_PORTB_BASE, GPIO_PIN_5 | GPIO_PIN_1);
	GPIOPadConfigSet(GPIO_PORTB_BASE, GPIO_PIN_5 | GPIO_PIN_1, GPIO_STRENGTH_2MA,
			GPIO_PIN_TYPE_STD_WPU);

	while (1) {
		value = GPIOPinRead(GPIO_PORTB_BASE, GPIO_PIN_5 | GPIO_PIN_1);
		if ((value & GPIO_PIN_1) == 0) {
			state ^= 4;
		}
		if ((value & GPIO_PIN_5) == 0) {
			state ^= 4;
		}
		GPIOPinWrite(GPIO_PORTB_BASE, GPIO_PIN_2, state);
		SysCtlDelay(10000000);

	}
}

When I debug, CCS show me this error :

I try to use LM FLash but It cannot get the value of register or MAC Address so  Debug Port Unlock is not worked

  • Hell Nhat

    Please follow the steps carefully as given in the following post

    e2e.ti.com/.../374640

    Also do make sure that when you connect the USB cable, the windows device manager recognizes the ICDI and COM port.

    Regards
    Amit
  • I read some but almost issues are used Debug Port Unlock, but my MAC Address is not showed, it's completely blank

    Here is when I connected my device , I'm using windows 10

  • Hello Nhat

    The Debug Port Unlock will erase all user committed registers as well. This is documented in the data sheet as well.

    Regards
    Amit
  • Did your board (ever) work?

    Was the code (you now show) the (real) code before your board "departed?"

    By the part number - it is assumed that yours is a Launch Pad. Is that correct? Have you another? (enables the determination of "board" or PC as (likely) problem source...
  • Yeah, you're right, I'm using Launch Pad EK-TM4C123GXL
    Code that I used for device is Lab6: Low Power Modes in LaunchPad Workshop


    But thanks to you , I remember that It is in hibernate state, so I pressed button reset , power off, power on device again , unlock debug port , and still hold button reset till when it show dialog to release button reset, now it works again,

    Thank you very much

  • Hello Nhat,

    When using low power mode, the system clock may be well below what can be sued to connect from the JTAG. The System clock is selected as Low power internal oscillator of 30K would not work with the JTAG TCK which is in MHz. This is a condition laid out in electrical section of the data sheet. The System clock must be 10x of the TCK.

    Regards
    Amit
  • Hi Amit,

    While USA is noted as, "litigious" society - it is doubtful that "system clock" can be "sued."   (clearly typo - "used" was meant" - yet the word play IS clever)

    There appears a RASH of such "Lock Outs" far higher here than on all other ARM Forums we visit, combined.

    Crack design team - while not taxed w/new additions (i.e. no evidence of such) may examine any "weakness w/in debug/program port" which so often causes dreaded "Lock Out."   That's serious - is it not - and while "duly noted" it remains, "duly continuing!" (its plague upon hapless users!)

    In fairness - under "paid IAR" w/J-Link - we rarely suffer lock-out.   And we always employ the defense mechanism offered by "JTAG-GPIO.C"

    Poster should consider "Splashing some green" upon post "Thanks to you" which stimulated his "fix."