HI
I am working with BLE CSCS example, and I found some problem during read cadence value. Simulator is changing values and I am observing situation: if cadence value is less than 50rpm occasionally shows 0rpm. I think that it occured when cumulative_crank_revs is not incerement during 1 seceond (BICYCLE_POWER_MEAS_INTERVAL).
Have anyone meet the same problem ?
Hi, I am using SDK12.1.0.
Ok, can you please specify the following?
Is it the "ble_app_cscs" example you are referring to?
By "cadence value", do you mean crank rev?
What is "BICYCLE_POWER_MEAS_INTERVAL"?
My code (using SDK version 12.1.0) looks like this;
static void csc_sim_measurement(ble_cscs_meas_t * p_measurement)
{
static uint16_t cumulative_crank_revs = 0;
static uint16_t event_time = 0;
static uint16_t wheel_revolution_mm = 0;
static uint16_t crank_rev_degrees = 0;
uint16_t mm_per_sec;
uint16_t degrees_per_sec;
uint16_t event_time_inc;
// Per specification event time is in 1/1024th's of a second.
event_time_inc = (1024 * SPEED_AND_CADENCE_MEAS_INTERVAL) / 1000;
// Calculate simulated wheel revolution values.
p_measurement->is_wheel_rev_data_present = true;
mm_per_sec = KPH_TO_MM_PER_SEC * sensorsim_measure(&m_speed_kph_sim_state,
&m_speed_kph_sim_cfg);
wheel_revolution_mm += mm_per_sec * SPEED_AND_CADENCE_MEAS_INTERVAL / 1000;
m_cumulative_wheel_revs += wheel_revolution_mm / WHEEL_CIRCUMFERENCE_MM;
wheel_revolution_mm %= WHEEL_CIRCUMFERENCE_MM;
p_measurement->cumulative_wheel_revs = m_cumulative_wheel_revs;
p_measurement->last_wheel_event_time =
event_time + (event_time_inc * (mm_per_sec - wheel_revolution_mm) / mm_per_sec);
// Calculate simulated cadence values.
p_measurement->is_crank_rev_data_present = true;
degrees_per_sec = RPM_TO_DEGREES_PER_SEC * 40;
crank_rev_degrees += degrees_per_sec * SPEED_AND_CADENCE_MEAS_INTERVAL / 1000;
cumulative_crank_revs += crank_rev_degrees / DEGREES_PER_REVOLUTION;
crank_rev_degrees %= DEGREES_PER_REVOLUTION;
p_measurement->cumulative_crank_revs = cumulative_crank_revs;
p_measurement->last_crank_event_time =
event_time + (event_time_inc * (degrees_per_sec - crank_rev_degrees) / degrees_per_sec);
event_time += event_time_inc;
}
Perhaps you could try replace your code with the code above.
Now I am using stock examle from SDK15. Just hardoce crank revolution = 40;
// Calculate simulated cadence values.
p_measurement->is_crank_rev_data_present = true;
degrees_per_sec = RPM_TO_DEGREES_PER_SEC * 23; //sensorsim_measure(&m_crank_rpm_sim_state, &m_crank_rpm_sim_cfg);
crank_rev_degrees += degrees_per_sec * SPEED_AND_CADENCE_MEAS_INTERVAL / 1000;
cumulative_crank_revs += crank_rev_degrees / DEGREES_PER_REVOLUTION;
crank_rev_degrees %= DEGREES_PER_REVOLUTION;
p_measurement->cumulative_crank_revs = cumulative_crank_revs;
p_measurement->last_crank_event_time =
event_time + (event_time_inc * (degrees_per_sec - crank_rev_degrees) / degrees_per_sec);
event_time += event_time_inc;
Plese look for screen recorder from Android app:
It looks like you have a different application than the one I'm using. Try downloading the "nRF Toolbox for BLE" application on your phone, and see if the problem persists.
I look like everything is fine with nRf Toolbox. But when I am using third-party app like "Strava", "Wahoo fitness" "Motosumo" this bug occured.
I suggest you use the nRF toolbox application with the cscs example. If you need your own functionality, you can implement it yourself by using the source code for the nRF toolbox found here,
github.com/.../Android-nRF-Toolbox
github.com/.../IOS-nRF-Toolbox
I suggest you use the nRF toolbox application with the cscs example. If you need your own functionality, you can implement it yourself by using the source code for the nRF toolbox found here,
github.com/.../Android-nRF-Toolbox
github.com/.../IOS-nRF-Toolbox
I know, but what with compatibily with third-party apps and BLE GATT specification ? Please look for thisscreen recorder from third-party apps
Hmm, that's strange. I installed the wahoo fitness app and tried the example and it worked for me. It reads 40 rpm all the time. Perhaps you can try reinstalling the SDK, and make sure you download it from this location http://developer.nordicsemi.com/nRF51_SDK/nRF5_SDK_v12.x.x/. Then you can compile the example unmodified and see if it works, and if it does you can then try to modify it and see if it still works.
Try to set other values from range 0 - 50rpm;
Still the same effect.stock example from SDK15, s132_nrf52_6.0.0_softdevice
Please try wit Wahoo ultility
I tried it, and I got the same result as you. It happens because last_crank_event_time isn't updated every time the measurement is sent to the phone application. This happens if the RPM is below 60.
If you want to know why, read this file
The crank measurement is handled in onCrankMeasurementReceived(). As for the Wahoo application, I assume the behavior is similar to nRF toolbox and that's the reason it reads 0 most of the time.
