how to use libuarte

[OldXiao]

I want to use the async driver,but did not find the example or explanation.

I have looked for the whole examples with "nrf_libuarte_async.h", found nothing,a little strange,I guess the NRF_LOG should useed this lib,but not check yet.

[OldXiao]

found one:nRF5_SDK_17.1.0_ddde560\examples\peripheral\libuarte.

defined :

NRF_LIBUARTE_ASYNC_DEFINE(m_libuarte, 0, 0,0,NRF_LIBUARTE_PERIPHERAL_NOT_USED, NRF_SDH_BLE_GATT_MAX_MTU_SIZE, 2)

error:

Build target 'UART2BLEnrf52810_xxaa'
compiling app_uarte.c...
..\..\..\app_uarte.c(7): error:  #94: the size of an array must be greater than zero
  NRF_LIBUARTE_ASYNC_DEFINE(m_libuarte, 0, 0,0,NRF_LIBUARTE_PERIPHERAL_NOT_USED, NRF_SDH_BLE_GATT_MAX_MTU_SIZE, 2)
..\..\..\app_uarte.c(7): error:  #94: the size of an array must be greater than zero
  NRF_LIBUARTE_ASYNC_DEFINE(m_libuarte, 0, 0,0,NRF_LIBUARTE_PERIPHERAL_NOT_USED, NRF_SDH_BLE_GATT_MAX_MTU_SIZE, 2)
..\..\..\app_uarte.c(7): error:  #20: identifier "NRFX_TIMER0_INST_IDX" is undefined
  NRF_LIBUARTE_ASYNC_DEFINE(m_libuarte, 0, 0,0,NRF_LIBUARTE_PERIPHERAL_NOT_USED, NRF_SDH_BLE_GATT_MAX_MTU_SIZE, 2)
..\..\..\app_uarte.c: 0 warnings, 3 errors
".\_build\UART2BLEnrf52810_xxaa.axf" - 3 Error(s), 0 Warning(s).

It is hard to understand the detail information:

/**
 * @brief Macro for creating instance of libuarte_async.
 *
 * Libuarte_async requires one timer-like peripheral (RTC or TIMER) for triggering RX timeout.
 * Macro will create instance only for peripheral which is used.
 *
 * @param _name        Instance name.
 * @param _uarte_idx   UARTE instance used.
 * @param _timer0_idx  TIMER instance used by libuarte for bytes counting.
 * @param _rtc1_idx    RTC instance used for timeout. If set to NRF_LIBUARTE_PERIPHERAL_NOT_USED
 *                     then TIMER instance is used or app_timer instance if _timer1_idx is also set
 *                     to NRF_LIBUARTE_PERIPHERAL_NOT_USED.
 * @param _timer1_idx  TIMER instance used for timeout. If set to NRF_LIBUARTE_PERIPHERAL_NOT_USED
 *                     then RTC instance is used or app_timer instance if _rtc1_idx is also set
 *                     to NRF_LIBUARTE_PERIPHERAL_NOT_USED.
 * @param _rx_buf_size Size of single RX buffer. Size impacts accepted latency between buffer
 *                     request and providing next buffer. Next must be provided within before
 *                     _rx_buf_size bytes is received.
 * @param _rx_buf_cnt  Number of buffers in the RX buffer pool. Size impacts accepted latency
 *                     between NRF_LIBUARTE_ASYNC_EVT_RX_DATA event and
 *                     @ref nrf_libuarte_async_rx_free.
 */
#define NRF_LIBUARTE_ASYNC_DEFINE(_name, _uarte_idx, _timer0_idx,\
                                  _rtc1_idx, _timer1_idx,\
                                  _rx_buf_size, _rx_buf_cnt) \
      STATIC_ASSERT(_rx_buf_cnt >= 3, "Wrong number of RX buffers");\
      STATIC_ASSERT(!((NRF_LIBUARTE_ASYNC_WITH_APP_TIMER == 0) && \
                    (_rtc1_idx == NRF_LIBUARTE_PERIPHERAL_NOT_USED) && \
                    (_timer1_idx == NRF_LIBUARTE_PERIPHERAL_NOT_USED)), \
                    "App timer support disabled");\
      NRF_LIBUARTE_DRV_DEFINE(CONCAT_2(_name, _libuarte), _uarte_idx, _timer0_idx);\
      NRF_QUEUE_DEF(uint8_t *, CONCAT_2(_name,_rxdata_queue), _rx_buf_cnt, NRF_QUEUE_MODE_NO_OVERFLOW);\
      NRF_BALLOC_DEF(CONCAT_2(_name,_rx_pool), _rx_buf_size, _rx_buf_cnt);\
      /* Create TIMER instance only if _timer1_idx != NRF_LIBUARTE_PERIPHERAL_NOT_USED */ \
      _LIBUARTE_ASYNC_EVAL(\
              NRFX_CONCAT_3(NRFX_TIMER, _timer1_idx, _ENABLED),\
              (STATIC_ASSERT((_timer1_idx == NRF_LIBUARTE_PERIPHERAL_NOT_USED) || (CONCAT_3(NRFX_TIMER,_timer1_idx, _ENABLED) == 1), "TIMER instance not enabled");\
               static const nrfx_timer_t CONCAT_2(_name, _timer) = NRFX_TIMER_INSTANCE(_timer1_idx);),\
              (/* empty */))\
      /* Create RTC instance only if _timer1_idx != NRF_LIBUARTE_PERIPHERAL_NOT_USED */ \
      _LIBUARTE_ASYNC_EVAL(\
              NRFX_CONCAT_3(NRFX_RTC, _rtc1_idx, _ENABLED),\
              (STATIC_ASSERT((_rtc1_idx == NRF_LIBUARTE_PERIPHERAL_NOT_USED) || (CONCAT_3(NRFX_RTC,_rtc1_idx, _ENABLED) == 1), "RTC instance not enabled");\
               static const nrfx_rtc_t CONCAT_2(_name, _rtc) = NRFX_RTC_INSTANCE(_rtc1_idx);),\
              (/* empty */))\
      _LIBUARTE_ASYNC_EVAL(NRFX_CONCAT_3(NRFX_TIMER, _timer1_idx, _ENABLED),\
              (/* empty */),\
              (_LIBUARTE_ASYNC_EVAL(NRFX_CONCAT_3(NRFX_RTC, _rtc1_idx, _ENABLED),(/* empty */), \
                   (APP_TIMER_DEF(CONCAT_2(_name,_app_timer)); \
                   nrf_libuarte_app_timer_ctrl_blk_t CONCAT_2(_name,_app_timer_ctrl_blk);))) \
      )\
      static nrf_libuarte_async_ctrl_blk_t CONCAT_2(_name, ctrl_blk);\
      _LIBUARTE_ASYNC_EVAL(\
              NRFX_CONCAT_3(NRFX_RTC, _rtc1_idx, _ENABLED), \
              (static void CONCAT_2(_name, _rtc_handler)(nrfx_rtc_int_type_t int_type);),\
              (/* empty */)) \
      \
      static const nrf_libuarte_async_t _name = {\
              .p_rx_pool = &CONCAT_2(_name,_rx_pool),\
              .p_rx_queue =  &CONCAT_2(_name,_rxdata_queue),\
              /* If p_rtc is not NULL it means that RTC is used for RX timeout */ \
              .p_rtc = _LIBUARTE_ASYNC_EVAL(NRFX_CONCAT_3(NRFX_RTC, _rtc1_idx, _ENABLED), (&CONCAT_2(_name, _rtc)), (NULL)),\
              /* If p_timer is not NULL it means that RTC is used for RX timeout */ \
              .p_timer = _LIBUARTE_ASYNC_EVAL(NRFX_CONCAT_3(NRFX_TIMER, _timer1_idx, _ENABLED), (&CONCAT_2(_name, _timer)), (NULL)),\
              /* If p_time and p_rtc is NULL it means that app_timer is used for RX timeout */ \
              .p_app_timer = _LIBUARTE_ASYNC_EVAL(NRFX_CONCAT_3(NRFX_TIMER, _timer1_idx, _ENABLED),\
	                    (NULL),\
	                    (_LIBUARTE_ASYNC_EVAL(NRFX_CONCAT_3(NRFX_RTC, _rtc1_idx, _ENABLED),(NULL), \
	                         (&CONCAT_2(_name,_app_timer)))) \
	            ),\
              .p_app_timer_ctrl_blk = _LIBUARTE_ASYNC_EVAL(NRFX_CONCAT_3(NRFX_TIMER, _timer1_idx, _ENABLED),\
	                    (NULL),\
	                    (_LIBUARTE_ASYNC_EVAL(NRFX_CONCAT_3(NRFX_RTC, _rtc1_idx, _ENABLED),(NULL), \
	                         (&CONCAT_2(_name,_app_timer_ctrl_blk)))) \
	            ),\
              .p_libuarte = &CONCAT_2(_name, _libuarte),\
              .p_ctrl_blk = &CONCAT_2(_name, ctrl_blk),\
              .rx_buf_size = _rx_buf_size,\
              _LIBUARTE_ASYNC_EVAL(\
                  NRFX_CONCAT_3(NRFX_RTC, _rtc1_idx, _ENABLED),\
                  (.rtc_handler =CONCAT_2(_name, _rtc_handler)),\
                  ()\
              )\
      };\
      /* RTC compare event is not periodic but need to be enabled again in the callback. */ \
      _LIBUARTE_ASYNC_EVAL(\
          NRFX_CONCAT_3(NRFX_RTC, _rtc1_idx, _ENABLED),\
          (\
             static void CONCAT_2(_name, _rtc_handler)(nrfx_rtc_int_type_t int_type)\
             { \
               (void)nrfx_rtc_cc_set(_name.p_rtc, 0, _name.p_ctrl_blk->timeout_us/32, true);\
               nrf_libuarte_async_timeout_handler(&_name);\
             }\
          ),\
          ()\
      )

I should define these instance first?

 * @param _uarte_idx   UARTE instance used.
 * @param _timer0_idx  TIMER instance used by libuarte for bytes counting.
 * @param _rtc1_idx    RTC instance used for timeout. If set to NRF_LIBUARTE_PERIPHERAL_NOT_USED
 *                     then TIMER instance is used or app_timer instance if _timer1_idx is also set
 *                     to NRF_LIBUARTE_PERIPHERAL_NOT_USED.
 * @param _timer1_idx  TIMER instance used for timeout. If set to NRF_LIBUARTE_PERIPHERAL_NOT_USED
 *                     then RTC instance is used or app_timer instance if _rtc1_idx is also set
 *                     to NRF_LIBUARTE_PERIPHERAL_NOT_USED.

[OldXiao]

Solved.

In order to use the Macro NRF_LIBUARTE_ASYNC_DEFINE,you have to confirm:

1) include all files needed:

nrfx_ppi.c

nrfx_timer.c

nrf_libuarte_drv.c

nrf_libuarte_async.c

(there is problem if you try to use RTC timer)

2)enable these drivers in sdk_config.h;

This is the main source of error.

As my case:

NRF_LIBUARTE_ASYNC_DEFINE(m_libuarte, 0, 1,    NRF_LIBUARTE_PERIPHERAL_NOT_USED, 2,  NRF_SDH_BLE_GATT_MAX_MTU_SIZE * 2, 3); 

I use UARTE0,TIMER1,TIMER2.

You should not just enbale NRFX drivers, you have to enable legacy TIMER1 & TIMER2 driver.

Problems come mainly from here.

The Macro does not think the TIMERx is enabled if you did not enable legacy drivers,and the tip info provided by NRF_LIBUARTE_ASYNC_DEFINE is meaningless.

These kind of info should include into the official explaination,I spend many hours to try error.