CC2564B custom board bring up issue

Vageesh KM

Other Parts Discussed in Thread: CC2564

Hi,

We are testing our custom designed proto board and had issues with the TI’s CC2564B(Dual-Mode Bluetooth controller) initialization.

RTS Pin of CC2564 is not becoming LOW as mentioned in the datasheet for successful initialization. Also tested our module according to the CC2564 testing guide wiki link (http://processors.wiki.ti.com/index.php/CC256x_Testing_Guide). As mentioned in the link, after the initialization process CC2564 is not pulling the RTS line LOW, that clearly indicates that Bluetooth controller is not getting initialized properly.

We have checked our Custom designed proto board and made sure that all the parameters mentioned in the testing guide is proper as below.

1) VDD_IN = 3.3V

2) VDD_IO = 1.8V

3) SLW_CLK = 32.768KHz ( Oscillator (1.8V) )

4) FAST_CLK = 26MHz ( Crystal )

5) nSTUD = GPIO _ MICRO _ CONTROLLER ( 1.8V with level shifter )

6) Using Hardware Flow Control

The UART communication(between CC2564 Bluetooth controller and STM32F4 Host controller) is done through level shifter from micro controller.

Kindly guide whether we are missing anything here.

over 8 years ago

0 Joseph Gigi over 8 years ago

TI__Guru* 85400 points

Hi Vageesh,

Can you confirm the slow clock accuracy (it should be +/- 250 ppm)?

Regards,
Gigi Joseph.

0 krishna narayanan over 8 years ago in reply to Joseph Gigi

Expert 1190 points

Hi Gigi,

I am Vageesh's Colleague.

The Accuracy of the Slow Clock is +/- 20 ppm.

Best,

Krish

0 Miguel over 8 years ago in reply to krishna narayanan

TI__Mastermind 23565 points

Krish,

Could you check the accuracy of the fast clock? Also, could you share a snapshot of the schematics around the CC2564 controller?

~Miguel

0 krishna narayanan over 8 years ago in reply to Miguel

Expert 1190 points

Hi Miguel,

Thanks for the reply.

Accuracy of the Fast clock is +/- 20 ppm and Slow Clock is also +/- 20ppm.

Attaching the

Figure 1: Schematic of CC2564

Figure 2: Schematic of Level Shifter for UART

Figure 3: Schematic of Level Shifter for nShutdown

Best,

Krish

0 Miguel over 8 years ago in reply to krishna narayanan

TI__Mastermind 23565 points

Hi Krish,

We don't recommend using auto-sense voltage translators on the UART lines since there may be some pin misconfiguration on the CC256x UART pins during initialization. I am not sure if this is the problem here, but could you try removing U8 and see if it solves the issue with RTS.

Regards,

~Miguel

0 krishna narayanan over 8 years ago in reply to Miguel

Expert 1190 points

Hi Miguel,

We tried removing U8 and replaced with the same level shifter used in CC2564QFN-EM board, but no luck. Still its not getting initialised. Any other Possibilities of error??

Require serious support as we are nearing Mass Production Deadline and Stuck with this problem from past two weeks.

Thanks in advance.

Best,

Krish

0 Miguel over 8 years ago in reply to krishna narayanan

TI__Mastermind 23565 points

Krish,

There Is nothing else required than the power supplies and clocks for the device to boot-up. Could you send us a screenshot of the initialization sequence? VIO, VBAT, nSHUTD, UART lines, slow clock and XTAL.

~Miguel

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CC2564B custom board bring up issue