CYW20819 Maximum UART baudrate

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ToKo_4602001
Level 4
Level 4
50 sign-ins 25 replies posted 25 sign-ins

I have found the following description in wiced_hal_puart.h

/******************************************************************************

* Function Name: wiced_hal_puart_configuration

***************************************************************************//**

* updates the baudrate, parity and stop bits as per received value

* \param baudrate - Desired rate in symbols/sec ex. 9600

* \param parity   - PARITY_ODD for odd parity, PARITY_EVEN for even parity,

*                   PARITY_NONE for no parity.

* \param stop_bit - STOP_BIT_1 for 1 stop bit, STOP_BIT_2 for 2 stop bits.

*

* \return BOOL32  - TRUE if the configuration was successfully set, FALSE

*                   otherwise.NOTE: For baudrate greater than 2.727272 Mb/sec

*                   use of 2 stop bits is mandatory due to hardware

*                  limitation.

********************************************************************************/

However I cannot find this limitation in the datasheet (Document Number: 002-22950 Rev. *E)

And there is the following description.

-----------------------------------------------------------------------------------------------------------------------------------

The UART physical interface is a standard, 4-wire interface (RX, TX, RTS, and CTS) with adjustable baud rates from

115200 bps to 3 Mbps.

-----------------------------------------------------------------------------------------------------------------------------------

Please show me if I can use 3 Mbps.

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1 Solution
DheerajPK_41
Moderator
Moderator
Moderator
750 replies posted 500 likes received 500 replies posted

Hi,

If it is regarding puart baud rate, the cut off is actually at 2.727272 Mb/sec. But when using 3M as baud rate, we need to add an extra stop bit which will effectively cuts the baud rate back to 2.727272 Mb/sec.

The description which you have copied is for HCI UART, which I believe support 3M baud rate as of now.

Thanks,

-Dheeraj

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2 Replies
DheerajPK_41
Moderator
Moderator
Moderator
750 replies posted 500 likes received 500 replies posted

Hi,

If it is regarding puart baud rate, the cut off is actually at 2.727272 Mb/sec. But when using 3M as baud rate, we need to add an extra stop bit which will effectively cuts the baud rate back to 2.727272 Mb/sec.

The description which you have copied is for HCI UART, which I believe support 3M baud rate as of now.

Thanks,

-Dheeraj

Thank you for this information.

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