RE: callback isn't optional in app_pwm_init

RK — Sun, 14 Jun 2015 11:59:30 GMT

Nothing at all to do with r2 and r3 silicon - all you have to do is look at the code for app_pwm_init and see the code says

ret_code_t app_pwm_init(app_pwm_t const * const p_instance, app_pwm_config_t const * const p_config,
                        app_pwm_callback_t p_ready_callback)
{
    ASSERT(p_instance);
    ASSERT(p_ready_callback);

So yes that's going to assert right away if p_ready_callback is NULL.

If you also check the two places in the code the callback is used, neither of them check for nil eg,

if (ticks == p_ch_cb->pulsewidth)
    {
        p_cb->p_ready_callback(p_instance->p_timer->instance_id);
        return NRF_SUCCESS;     // No action required.
    }

so NULL Is not an option. Clearly the header file is just wrong in this instance. You can remove the assert() and add a guard to the two places the callback is called only to call if not NULL, or just supply a simple do-nothing handler.