How to unblock the CPU during connection intervals with S110 v7.1.0?

Question

How do I unblock the CPU with the S110 v7.1.0?

Håkon Alseth · Accepted Answer

Hi, 
 To disable the CPU blocking with S110 v7.1.0 or newer, you will have to use this API call: 
 /**@brief Set a BLE option.
 *
 * @details This call allows the application to set the value of an option.
 *
 * @param[in] opt_id Option ID.
 * @param[in] p_opt Pointer to a ble_opt_t structure containing the option value.
 *
 * @retval ::NRF_SUCCESS Option set successfully.
 * @retval ::NRF_ERROR_INVALID_ADDR Invalid pointer supplied.
 * @retval ::BLE_ERROR_INVALID_CONN_HANDLE Invalid Connection Handle.
 * @retval ::NRF_ERROR_INVALID_PARAM Invalid parameter(s) supplied, check parameter limits and constraints.
 * @retval ::NRF_ERROR_INVALID_STATE Unable to set the parameter at this time.
 * @retval ::NRF_ERROR_BUSY The stack is busy or the previous procedure has not completed.
 */
SVCALL(SD_BLE_OPT_SET, uint32_t, sd_ble_opt_set(uint32_t opt_id, ble_opt_t const *p_opt));
 
 The options available as of now is only one, which is the mutual exclusion of radio activity and CPU usage (read block/unblock CPU in connection interval): 
 /**@brief Common Option IDs.
 * IDs that uniquely identify a common option.
 */
enum BLE_COMMON_OPTS
{
 BLE_COMMON_OPT_RADIO_CPU_MUTEX = BLE_OPT_BASE /**< Radio CPU mutex option. @ref ble_common_opt_radio_cpu_mutex_t */
};
 
 And here's a small snippet on how to disable the CPU blocking: 
 uint32_t opt_id = BLE_COMMON_OPT_RADIO_CPU_MUTEX;
ble_opt_t cpu_blocking_enabled;
cpu_blocking_enabled.common_opt.radio_cpu_mutex.enable = 0;
ble_stack_init();
err_code = sd_ble_opt_set(opt_id, &cpu_blocking_enabled);
/* continue init */
 
 Cheers,
Håkon 
 =============================== 
 Additional images showing how the CPU availability is improved when advertising (same applies when in connection): 
 Before (CPU blocked during radio active):
 
 After (Concurrent CPU when radio is active):
 
 Black part showing the latency when CPU is blocked.
[ADDED]:
On the second trace, the CPU is still blocked at some periods because it's the softdevice active and preparing the radio packet, no the radio itself. 
 Cheers, 
 Hung Bui

How to unblock the CPU during connection intervals with S110 v7.1.0?

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