Tiva C Series TM4C1294 Connected LaunchPad

 Again and forever.... Please MORE MORE DETAIL!!!!!

Siarhei Nestserau said:

When I try to configure PQ4 pin as DIVSCLK (Alternate Function), controller halt and board disconnected  from USB.

 From ICDI? From OTG, please describe..

Siarhei Nestserau said:

Just LM Flash Programmer can help restore communication, but clear all flash memory include MAC address.  What is the problem? Thanks.

 What can be the problem...

 How you use LMFlash?

 If you unlock clear, then ALL DATA including MAC address register got clean. SO reload MAC with LM then code.

Hi Siarhei,

     As Roberto mentioned "provide more details". Also, post your code here, so others can review it.

     Since you are new in the forum, see links below.

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-kel

Hi, guys,

I'm using the following code to enable the DIVSCLK on EK-TM4C1294XL rev-D board. I never get it work because it will loss the connection and lock the MCU.

SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOQ);
GPIOPadConfigSet(GPIO_PORTQ_BASE, GPIO_PIN_4, GPIO_STRENGTH_2MA, GPIO_PIN_TYPE_STD);

GPIOPinConfigure(GPIO_PQ4_DIVSCLK);

GPIODirModeSet(GPIO_PORTQ_BASE, GPIO_PIN_4, GPIO_DIR_MODE_HW);

SysCtlClockOutConfig(SYSCTL_CLKOUT_EN | SYSCTL_CLKOUT_SYSCLK, 100);

If I remove the GPIOPadConfigSet() function, it seems no error but I couldn't see any waveform on PQ4.

 SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOQ);
// GPIOPadConfigSet(GPIO_PORTQ_BASE, GPIO_PIN_4, GPIO_STRENGTH_2MA, PIN_TYPE_STD);
 GPIOPinConfigure(GPIO_PQ4_DIVSCLK);
 GPIODirModeSet(GPIO_PORTQ_BASE, GPIO_PIN_4, GPIO_DIR_MODE_HW);
 SysCtlClockOutConfig(SYSCTL_CLKOUT_EN | SYSCTL_CLKOUT_SYSCLK, 100);

My code is base on the spiloopback_TM4C1294NCPDT example with TI RTOS.

Could you post your working code for DIVSCLK if you had it works for you?

Thanks in advance.

Ron

Hello Ron,

The issue that you are facing is because on the TM4C129 LaunchPad the pin PQ4 is for detecting a OC fault. When you use it for DIVSCLK the toggle on the signal causes problem with the TPS switch.

The only way to workaround this is to remove the component U4 and then run a wire from the JP1 ICDI to Pin-7 pad of the removed U4 component trace.

Regards

Amit

Amit Ashara said:

Hello Ron,

The issue that you are facing is because on the TM4C129 LaunchPad the pin PQ4 is for detecting a OC fault. When you use it for DIVSCLK the toggle on the signal causes problem with the TPS switch.

The only way to workaround this is to remove the component U4 and then run a wire from the JP1 ICDI to Pin-7 pad of the removed U4 component trace.

Regards

Amit

Hello Jrmymllr,

Yes, it is easy to cut the trace but when it comes back to putting it sometimes it is a lot harder. Removing the U4 component allows to solder it back in. Both solutions work.

Regards

Amit