UART and UARTE peripherals

[danmcb]

I've asked before about these two peripherals, the way they are presented is a little confusing.

I understand that UARTE has DMA possibilities, UART doesn't. Also that in effect there is only one UART on the chip.

In the case that I just want a very simple UART for debugging purposes, with the minimum of config and so on - what is recommended?

Is UARTE a superset of UART, and can be setup as a simple peripheral without using the DMA stuff?

Is it recommended in new designs to use UARTE over UART in new designs? I ask because much UART documentation and driver code seems to be in legacy status now.

Thanks for clarifying.

[mrono]

The way I look at UART/UARTE is that there is only one peripheral with two different access methods.

If you access the peripheral using UARTE-> -registers, DMA will be enabled automatically. And similarly if you use UART-> -registers, DMA will be disabled.

Both should be fairly equal in terms of complexity for a simple debug uart.

[danmcb]

there is this though - a flag to turn off DMA use.

/**@brief Structure for UART configuration. */

typedef struct

{

    uint32_t            pseltxd;            ///< TXD pin number.

    uint32_t            pselrxd;            ///< RXD pin number.

    uint32_t            pselcts;            ///< CTS pin number.

    uint32_t            pselrts;            ///< RTS pin number.

    void *              p_context;          ///< Context passed to interrupt handler.

    nrf_uart_hwfc_t     hwfc;               ///< Flow control configuration.

    nrf_uart_parity_t   parity;             ///< Parity configuration.

    nrf_uart_baudrate_t baudrate;           ///< Baudrate.

    uint8_t             interrupt_priority; ///< Interrupt priority.

#if defined(NRF_DRV_UART_WITH_UARTE) && defined(NRF_DRV_UART_WITH_UART)

    bool                use_easy_dma;

#endif

} nrf_drv_uart_config_t;

[mrono]

I think that is just the Nordic uart driver's way of choosing either uart or uarte.

[danmcb]

no, there are separate files, typedefs, everything, for UART and UARTE.