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Hello, I used your example to configure the LIS2DS12, in single TAP mode, but the INT1 pin always remains high even when reading the TAP_SRC register. Could you give me some suggestions of what is missing in the configuration?

Associate III

Single-tap example

Hereafter an example code which implements the SW routine for single-tap detection.

1. Write 60h in CTRL1

// Turn on the accelerometer

// ODR = 400 Hz, FS = ±2 g

2. Write 38h in CTRL3 // Enable tap detection on X, Y, Z-axis

3. Write 09h in TAP_6D_THS // Set tap threshold

4. Write 06h in INT_DUR // Set quiet and shock time windows

5. Write 00h in WAKE_UP_THS // Only single tap enabled (SINGLE_DOUBLE_TAP = 0)

6. Write 40h in CTRL4 // Single-tap interrupt driven to INT1 pin

ST Employee

Hi @FBald.1​ ,

I suggest you to consider the C implementation of the "Single Tap" feature on Github --> lis2ds12_tap_single.c

This code implements not only the configuration, but also the main loop for the interrupt management and clearing.

Here below the detailed script:

/* Main Example --------------------------------------------------------------*/
void lis2ds12_single_tap_(void)
  /* Initialize mems driver interface */
  stmdev_ctx_t dev_ctx;
  dev_ctx.write_reg = platform_write;
  dev_ctx.read_reg = platform_read;
  dev_ctx.handle = &SENSOR_BUS;
  /* Check device ID */
  lis2ds12_device_id_get(&dev_ctx, &whoamI);
  if (whoamI != LIS2DS12_ID)
    while (1) {
      /* manage here device not found */
  /* Restore default configuration */
  lis2ds12_reset_set(&dev_ctx, PROPERTY_ENABLE);
  do {
    lis2ds12_reset_get(&dev_ctx, &rst);
  } while (rst);
  /* Set XL Output Data Rate */
  lis2ds12_xl_data_rate_set(&dev_ctx, LIS2DS12_XL_ODR_400Hz_HR);
  /* Set 2g full XL scale */
  lis2ds12_xl_full_scale_set(&dev_ctx, LIS2DS12_2g);
  /* Enable Tap detection on X, Y, Z */
  lis2ds12_tap_detection_on_z_set(&dev_ctx, PROPERTY_ENABLE);
  lis2ds12_tap_detection_on_y_set(&dev_ctx, PROPERTY_ENABLE);
  lis2ds12_tap_detection_on_x_set(&dev_ctx, PROPERTY_ENABLE);
  lis2ds12_4d_mode_set(&dev_ctx, PROPERTY_ENABLE);
  /* Set Tap threshold to 01001b, therefore the tap threshold is
   * 562.5 mg (= 9 * FS_XL / 2 5 )
  lis2ds12_tap_threshold_set(&dev_ctx, 0x09);
  /* Configure Single Tap parameter */
  //lis2ds12_tap_dur_set(&dev_ctx, 0x0);
  lis2ds12_tap_quiet_set(&dev_ctx, 0x01);
  lis2ds12_tap_shock_set(&dev_ctx, 0x02);
  /* Enable Single Tap detection only */
  lis2ds12_tap_mode_set(&dev_ctx, LIS2DS12_ONLY_SINGLE);
  /* Wait Events */
  while (1) {
    lis2ds12_all_sources_t all_source;
    lis2ds12_all_sources_get(&dev_ctx, &all_source);
    /* Check if Single Tap events */
    if (all_source.tap_src.single_tap) {
      sprintf((char *)tx_buffer, "Tap Detected\r\n");
      tx_com(tx_buffer, strlen((char const *)tx_buffer));

Let me please know if you can find this code useful.