Tiva c off computer powering

So little detail in your request - makes remote diagnostics unnecessarily complex.

Almost sounds as if you're attempting to power your MCU (we're not told if this is custom board or pro kit) from 5V.

In dinosaur era - MCUs (and most other ICs) did power directly from 5V.  Modern times saw the migration to 3V3 - and even lower.  If you've powered that MCU from 5V - without imposing the (usual) 3V3 Regulator between - may I request an aisle seat for MCU's funeral?  (will have proper, black jacket cleaned)

Some attention to detail (reading) is required for these, "beyond Arduino" devices...

Hi Thero,

      Are you using a Tiva kit or a custom Tiva board. If you are using a Tiva kit, which one? Launchpad?(already mentioned by cb1)

      What code are you loading to your Tiva board?

      Details required when asking for help. See, link below.

      Information to provide when asking for help

-kel 

Kel - glad you're here - I cede this hi-tech episode to you.  (but do not poach my aisle seat - reserved for hasty exit - after MCU is deposited 6' under...)

i am using Tiva™ C Series LaunchPad Evaluation Kit     http://www.ti.com/tool/ek-tm4c123gxl

bought  straight from texas instruments.what code i'm i loading?..i'm not sure if i understand your question,i made a wall tracking robot with ultrasonic sensors

thanks for the replies

I am using code composer studio,the program seems to run well just after putting the program into the MCU but immediately after i remove the USB cable from the computer and try to power it with an external power supply of 5V it doesnt run even if i put back the mcu back into the computer it wont run.I will have to re-write the program again to the mcu

Thero Kemelo said:

...made a wall tracking robot with ultrasonic sensors

I may move that aisle seat to the very rear now...(hopefully out of harm's/robot's way) although the MCU may have escaped life-support due to the presence of a proper VReg upon a "pro" board.

This one all yours, Kel....

Hi Thero,

I have not tried to run my TI kits using external power. However, there should be no problem powering your Tiva Launchpad from an external 5V power supply, as there is a 3.3V voltage regulator at the Tiva Launchpad. Does the green power led light up, when you power your launchpad from an external +5V source?

Try, known working example programs, like blinky and uart_echo, while the Tiva Launchpad is powered from an external +5V power supply.

If the known working example programs work at your Tiva Launchpad, which is powered from external +5V source, then it is possible that your startup file for your "wall tracking robot" program, is the problem.

-kel

the green led does power up from the external +5V source...let me try the known working examples