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6 years, 3 months ago.
Cannot get neither onDataRead() nor setReadAuthorizationCallback() to work with nrf52832
I need a callback function to execute when a data read is performed from the Client via nrf Connect on Android. I have tried two methods:
1. using the onDataRead() function in a manner similar to onDataWritten(). The function onDataWritten() works fine. I have attempted to set a callback function for onDataRead with: ble.gattServer().onDataRead(onDataRead) in the bleInitComplete function:
include the mbed library with this snippet
#include "mbed.h" void bleInitComplete(BLE::InitializationCompleteCallbackContext *params) { ble.gattServer().onDataRead(onDataRead); ....
The callback looks like:
include the mbed library with this snippet
#include "mbed.h" void onDataRead(const GattReadCallbackParams *params) { if (params->handle == BLEServicePtr->readBatteryLevelCharacteristicHandle()) { BLEServicePtr->updateBatteryLevel(0x08); } BLEServicePtr->updateBatteryLevel(0x08); printf("onDataRead works \r\n"); }
The callback is never called.
2. I have attemped using the setReadAuthorizationCallback(). The first item is in the initializer of my service class and the second in the .cpp:
include the mbed library with this snippet
#include "mbed.h" readBatteryLevelCharacteristic.setReadAuthorizationCallback(this, &BleService::onDataRead_2); void BleService::onDataRead_2(GattReadAuthCallbackParams* event) { BLEServicePtr->updateBatteryLevel(0x08); }
I am working with mbed 5.9.1 in Eclipse on an nrf52832. Any insight into the use of the onDataRead and/or setReadAuthorizationCallback functions would be appreciated.
Thank you
2 Answers
5 years, 8 months ago.
I've got setReadAuthorizationCallback() to work with nrf52. You have to set it before adding the Characteristic to GattService.
5 years, 7 months ago.
I am also trying to figure out why this feature is not working. Here is what I've discovered so far. Here is an implementation of onDataRead() in the GattServer.h file in mbed-os:
OnDataRead
/** * Set an event handler that monitors attribute reads from connected clients. * * @param[in] objPtr Pointer to the instance that is used to invoke the * event handler (@p memberPtr). * @param[in] memberPtr Event handler being registered. It is a member * function. */ template <typename T> ble_error_t onDataRead( T *objPtr, void (T::*memberPtr)(const GattReadCallbackParams *context) ) { if (!isOnDataReadAvailable()) { return BLE_ERROR_NOT_IMPLEMENTED; } dataReadCallChain.add(objPtr, memberPtr); return BLE_ERROR_NONE; }
but the problem is that the function inOnDataReadAvailable() is set to false unless it is over ridden somewhere. Still trying to figure out what to do from here.
isOnDataReadAvailable
/** * Indicate if the underlying stack emit events when an attribute is read by * a client. * * @attention This function should be overridden to return true if * applicable. * * @return true if onDataRead is supported; false otherwise. */ virtual bool isOnDataReadAvailable() const { /* Requesting action from porters: override this API if this capability is supported. */ return false; }
Looks like the IsOnDataRead() needs to be overrided to return true somewhere.
Did you find a solution? I am getting stuck at the same problem. PUSH
posted by Wenzel Reichmuth 25 Jan 2019