After running Project0 in example, Tiva doesn't works with j-link SWD mode.

Yangrae Jung

Other Parts Discussed in Thread: TM4C1294NCPDT, SEGGER, EK-TM4C1294XL

Hi Everyone.

I have some problem. My chip is TM4C1294NCPDT.

My customize board has 25Mhz crystal with 12 pF, and I use the J-link with SWD.

First time. I connected SWD(j-link) to board. and Ioad the Project0 from example for TM4C1294xl Board. Click the debug button. Upload is well.and CCS was waiting for Debug with CCS debug mode.
So I clicked the redbutton (RUN). but board was stop.

and then, I cannot connect board anymore.

Error is below

CORTEX_M4_0: Error: Stat [ JLINKARM_IsHalted() call ] failed!
CORTEX_M4_0: Unable to determine target status after 20 attempts

And error in J-commander is below

Found SWD-DP with ID 0x2BA01477

****** Error: DAP error while reading AHB-AP IDR.
Found SWD-DP with ID 0x2BA01477
Found SWD-DP with ID 0x2BA01477
Found SWD-DP with ID 0x2BA01477
Can not connect to target.

I don't know the reason.

I just guess that reason is probably some code maybe changed the clock setting. maybe.. like below code.

(ui32SysClock = SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ | SYSCTL_OSC_MAIN | SYSCTL_USE_PLL | SYSCTL_CFG_VCO_480), 120000000);)

over 8 years ago

0 Amit Ashara over 8 years ago

TI__Guru**** 244400 points

Hello Yangrae

Can you check if the Crystal is oscillating with 25MHz. The other thing to check is if you have populated the RBIAS resistor for the TM4C129x part

0 cb1 over 8 years ago in reply to Amit Ashara

Guru 47900 points

And - should this chip behave similarly to (past) LM3S, LX4F, TM4C123 - an improper setting to Port-C (PC0-PC3) will also "break" communications.

Posters must use great care when manipulating System Clock and/or Port-C.

0 Amit Ashara over 8 years ago in reply to cb1

TI__Guru**** 244400 points

Hello cb1

Good point. We do not know if the Port C has been modified.

0 Petrei over 8 years ago

Guru 26105 points

Hi,

AFAIK the CCS does not work with Jlink. Are your claims about that real?

0 Yangrae Jung over 8 years ago in reply to Amit Ashara

Prodigy 60 points

Thank you for reply.

Actually. I didn't have 25Mhz Crystal. So Crystal is in board from EK-TM4C1294XL, :) maybe Crystal is correct.

RBIAS is already populated. because my application is for Ethernet environments.

I just think reason is that crystal is not near from MCU, about 10mm from crystal.

do i need change the CL Capacitor ? or not?

or other reason

Sincerly!

0 Yangrae Jung over 8 years ago in reply to cb1

Prodigy 60 points

Thank you!

0 Amit Ashara over 8 years ago in reply to Yangrae Jung

TI__Guru**** 244400 points

Hello Yangrae

1. For Ethernet 25MHz is mandatory
2. Lack of CL is a problem. 10 mm may not be.

Please refer to the System Design Guidelines for TM4C129x

Arm-based microcontrollers

Arm-based microcontrollers forum

After running Project0 in example, Tiva doesn't works with j-link SWD mode.