CC2564: CC2564 and MSP430F5438A Bluetooth Stack Init Failed: -4

Sooraj Gopakumar

Part Number: CC2564
Other Parts Discussed in Thread: MSP430F5438A, , , , CC256XMSPBTBLESW

Hi,

I have been trying to run the SPP demo for CC2564 and MSP430F5438A.
I have followed the steps mentioned in
processors.wiki.ti.com/.../CC256x_MSP430_TI_Bluetooth_Stack
and
processors.wiki.ti.com/.../CC256x_TI_Bluetooth_Stack_SPPDemo_App
After debug, when I run the code, I am getting Stack Init Failed: -4 over the UART in the terminal.

I am using MSP-TS430-Pz5x100 breakout board that is compatible with MSP430F5438A. I have connected the CC2564MODNEM board to the MSP via the EM connectors.
After studying the schematics of MSP-EXP430F5438 Experimenter Board, I have given the following pin connections (from CC2564 to MSP430F5438A).
UART_CTS : P1.4, Pin 21
UART_RX : P1.5, Pin 22
UART_TX : P1.6, Pin 23
UART_RTS : P8.1, Pin 58
nSHTD : P8.2, Pin 59

The following are the connections that I am using to get the serial port messages via Teraterm (9600, 8, n, 1)
USB_RXD : Pin 54
USB_TXD : Pin 53

I have checked the startup procedure for the module and everything seems to be fine.
I verified the slow clock and the frequency is 32,768 Hz. I cannot check the fast clock since the eval board has CC2564MODN for which the fast clock is internal.
After Debug, when I run the code, the UART_RTS gets pulled low after nSHTD is pulled high (below is screenshot from scope, channel 1 is UART_RTS and channel 2 is nSHTD).

UART_RTS remains low for a few seconds after which it goes back to high and the following error message is displayed on Teraterm.

I am directly dumping the given sample code that comes with the bluetopia stack as mentioned in the tutorial without any modification whatsoever.

I have been stuck in this state for over a month and I am totally clueless how to move forward.
I read many discussions on the forum with the same error code but those fixes don't seem to work for me. Please help. Any suggestions would be of great help.

Thanks,
Sooraj

over 9 years ago

0 Vihang Parmar over 9 years ago

TI__Mastermind 29321 points

Hi Sooraj,

For the Stack Init Failed: -4 error, you might want to verify the below items.

- UART connections are configured correctly. Please refer to the CC256XMSPBTBLESW Sample applications for reference.
- The voltage supply to powering up the module is stable.
- Slow clock signal is stable before the nSHUTD pin is pulled high.

The -4 error is related to the HCI transport layer. So you might want to verify the above items.

Best regards,
Vihang

0 Sooraj Gopakumar over 9 years ago in reply to Vihang Parmar

Prodigy 210 points

Hi Vihang,

As per the testing guide, HCI_RTS will be pulled low only if the clock and voltage supply are stable before nSHTD. The RTS is getting pulled low as shown in the scope screenshot I attached, which means that the startup procedure was successful. I shall check the UART connections once again.

thanks,
Sooraj

0 Sooraj Gopakumar over 9 years ago in reply to Vihang Parmar

Prodigy 210 points

The MSP430 is running on 32.768kHz crystal oscillator. Does the MSP need more clock speed to communicate with CC2564? Is that why it gives error code -4?

0 Sooraj Gopakumar over 9 years ago in reply to Sooraj Gopakumar

Prodigy 210 points

Hi,

I have verified the UART connections and everything seems to be fine, but I am still getting the same error. I am starting to wonder if the clock frequency is the issue.

0 Vihang Parmar over 9 years ago in reply to Sooraj Gopakumar

TI__Mastermind 29321 points

Hi,

The UART baud rate accuracy could cause this issue. Have you been able to verify the baud rate using an oscilloscope or a logic analyzer?
The Section 5.7.3.1 of the CC2564B datasheet lists timing characteristic including baud rate accuracy per byte and per bit. Since the initial baud rate is 115200 bps, you can see from scope/logic analyzer readings if the accuracy requirement if off.

Best regards,
Vihang

0 Sooraj Gopakumar over 9 years ago in reply to Vihang Parmar

Prodigy 210 points

Hi,

The issue was very trivial. I got the RX and TX of the UART lines wrong. Swapping them solved the issue. Now it is communicating fine. Thanks

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CC2564: CC2564 and MSP430F5438A Bluetooth Stack Init Failed: -4