Need clarification on PUART RTS/CTS flow control support

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Anonymous
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In the PUART API, there are bunch of function calls and definition related with RTS/CTS as follows.

void puart_flowOn(void);

void puart_flowOff(void);

BOOL32 puart_checkCtsPortPin(UINT8 ctsPortPin);

BOOL32 puart_checkRtsPortPin(UINT8 rtsPortPin);

BOOL32 puart_selectUartPads(UINT8 rxdPortPin, UINT8 txdPortPin, UINT8 ctsPortPin, UINT8 rtsPortPin);

DEFAULT_P_UART_HWFLOWCONTROLWATERMARK = 13

And, 20732/20737 databook includes

  - Pin description of RTS and CTS

  - UART timing diagram with RTS and CTS

And, WICED Smart Hardware Interfaces has PUART mux options including RTS/CTS pins.

So, it seemed obvious that RTS/CTS is supported by hardware and firmware.

However, I found a couple of comments in this forum that says RTS/CTS is not available to PUART.

I am confused.

Can you please provide a clarification/confirmation on this?

Is UART RTS/CTS flow control supported by PUART?

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MichaelF_56
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Upon doing some research internally on the subject of flow control, it appears that flow control is not available via the PUART on the module.  This is why the RTS pin no longer appears as a GPIO option in the module datasheet.

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MichaelF_56
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Upon doing some research internally on the subject of flow control, it appears that flow control is not available via the PUART on the module.  This is why the RTS pin no longer appears as a GPIO option in the module datasheet.

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Anonymous
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So, PUART RTS/CTS is not available on the module, but it is available on QFN package.

Is that correct?

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Correct.

P1 (Referenced int he HW interfaces document) is tied internally to the WP function of the internal EEPROM, so flow control is not available on the module. A while back we had to remove this from the datasheet as discussed in this thread: Re: BCM20732S UART RTS pin

How about using CTS on P3 and allocating another GPIO to do the RTS? I do see the CTS still being available in the documentation of the 20737S. I have the feeling we can catch the interrupt register and figure out if CTS is up.

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Take a look at the HW interfaces guide here (Pages 15/16): WICED™ Smart Hardware Interfaces

Recall that only horizontal combinations in black are permitted.RTS is assigned to P1, which is used by WP on the EEPROM within the module as previously noted.  It does appear that CTS is still available.

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