CC2640: Module don't start (no bootloader, no RF activity)

Vladimir Aparin

Part Number: CC2640
Other Parts Discussed in Thread: CC2650

Hello

We made Beacon design based on SensorTag 2 design.
We just change antenna to chip and add some interfaces (UART fot bootloader).

We got very strange behavior showing in 2 aspects:

no activity on UART pins in bootloader
no RF activity at all

We can access SoC through JTAG (program flash, start debug). But nothing happens more.
It's very strange, because in our first revision of PCB RF working good (so firmware is correct). We just replace inverted-F antenna to chip ALA621C4

It's need to be pointed, that boot loader hasn't working on first PCB revision too. When we connect external SoC to launchpad Rx/Tx and launchpad power we don't see anything. When SoC on Launchpad in the same conditions are booting properly.

Can TI check our design (see attachment bellow) and give us some advice about this situation?

Beacon.pdf

over 9 years ago

0 Fredrik K over 9 years ago

TI__Guru** 106705 points

Hi Vladimir,

How do you know the bootloader is not working? Are you following the instructions in www.ti.com/.../swra466 and www.ti.com/lit/pdf/swcu117 bootloader chapter?

What do you mean by "nothing happens" when you are running debug? What SW are you using, and what is supposed to happen?

Cheers,
Fredrik

0 Vladimir Aparin over 9 years ago in reply to Fredrik K

Expert 2610 points

Hi Fredrik,

I think I should make some clarifications.

About bootloader: yes, we are using this instructions and try some other tools too (like SmartRF FlasH Programmer2). All ot them produces the same result - external CC2640 don't make any activity on Rx/Tx lines and hasn't commuticate with master. When we connected internal CC2640 from launchpad, all's working good.
About nothing happend means there are no activity on Rx/Tx pins and in RF. We can start debug of program, but we can't see any manifest of working besides the JTAG. We can't see anything on UART and in RF. It's need to be pointed, that we have 3 PCB's with the same behavior.

0 Fredrik K over 9 years ago in reply to Vladimir Aparin

TI__Guru** 106705 points

Hi Vladimir,

Are you using the correct UART pins for the bootloader?

What SW are you using? And what QFN package and RF configuration do you have in your custom board?

Cheers,
Fredrik

0 Vladimir Aparin over 9 years ago in reply to Fredrik K

Expert 2610 points

Hi Fredrik,

Yes we are using the DIO1/DIO0 for UART pins as listed in table 8 in www.ti.com/.../swra466a.pdf for QFN32/5x5.

If you ask about software (firmware) in SoC - we are using custom software (it's working correctly on previous PCB revision). We got an error only when transfer (copy) our project from Eagle to Altium (Schematics are the are the same and copied CC2650STK-RD in most).
If you ask about software on PC for bootloader - we are try www.ti.com/.../swra466

RF configuration - differential without external bias. You can see our schematics in topic in attachment. We copy design CC2650STK-RD and replace inverted-F antenna to chip antenna from Amotech.

0 Vladimir Aparin over 9 years ago in reply to Vladimir Aparin

Expert 2610 points

We trying use another one antenna from Molex. But result are still the same - No RF activity.

0 Fredrik K over 9 years ago in reply to Vladimir Aparin

TI__Guru** 106705 points

Hi Vladimir,

Have you verified that the HW is good? All supply pins have the correct voltage and so on?

Can you control the board from SmartRF Studio?

Cheers,
Fredrik

0 Vladimir Aparin over 9 years ago in reply to Fredrik K

Expert 2610 points

Hi Fredrik,

Yes we are checked voltages. All of them looking good:
VCC = 3.3 V
VDDS = 3.3 V
DCDC_SW = 1.68 V
VDDR = 1.68 V.
Voltage are the same as on first working revision.

If DC/DC turned off voltages are the same and the are still no RF.

0 Vladimir Aparin over 9 years ago in reply to Fredrik K

Expert 2610 points

Fredrik

we try work through SmartRF Studio too.
Result the same - first revision of PCB can send and receive packets to/from RF. New PCB - not.
I think that it should be something wrong with PCB or IC, but we are still don't understand what.
Can you check our design?

0 Luu Vy over 9 years ago in reply to Vladimir Aparin

Expert 2225 points

Hi Vladimir Aparin
Do Tasks of TI-RTOS work normally when you debug your code?

0 Dmitry Kuzmin over 9 years ago in reply to Luu Vy

Prodigy 65 points

Hi, Luu
Yes, tasks work normally

0 Fredrik K over 9 years ago in reply to Vladimir Aparin

TI__Guru** 106705 points

Hi Vladimir,

You do have ground vias in the ground pad, right? I cannot see them in the layout drawing.

Are you sure the 24 MHz crystal starts up?

Regards,
Fredrik

0 Vladimir Aparin over 9 years ago in reply to Fredrik K

Expert 2610 points

Hi Fredrick,

Sure we have vias to ground pad.

We'll check crystal that they start one more time.
As I can see in TRM there are one HF clock for MCU core and RF core. So I think that if program in MCU core working properly that crystal must work.
Can you recommend us special way to check that crystal work as expected?

BR, Vladimir

0 Fredrik K over 9 years ago in reply to Vladimir Aparin

TI__Guru** 106705 points

Hi Vladimir,

The best way is to use a spectrum analyzer to sniff the crystal.

BR,
Fredrik

0 Vladimir Aparin over 9 years ago in reply to Fredrik K

Expert 2610 points

Hello Fredrick.

We don't have spectrum analyzer. Only oscilloscope.

We trying to check crystals by them. We don't see oscillating .

How we can be sure, that our crystals choosed right? We trying 2 variants meets requirements in datasheet by accuracy and load. But in both cases cc2650 don't send anything in RF.

Bluetooth®︎

Bluetooth forum

CC2640: Module don't start (no bootloader, no RF activity)