I am trying to do a GATT write operation in a BLE after Notification where I am getting the value from server. The write operation works fine when there is no prior GATT operation like Notification. So this is the code where I am reading the value through notification
public async Task ReadConfigData(ICharacteristic characteristics)
{
if (characteristics != null)
{
try
{
await _adapter.ConnectToDeviceAsync(_device);
characteristics.ValueUpdated += (o, e) =>
{
Device.BeginInvokeOnMainThread(async () =>
{
//var readvalue2 = characteristics.Value;
var bytes = e.Characteristic.Value;
//var readvalue = await characteristics.ReadAsync();
BLEresultnew = System.Text.Encoding.UTF8.GetString(bytes);
Console.WriteLine(BLEresultnew);
//if(BLEresultnew.Contains("start"))
//{
concat += BLEresultnew;
//}
});
};
await characteristics.StartUpdatesAsync();
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
This is how I am doing the write operation
public async task WriteDataAsync(String data)
{
if (_characteristicsBLE != null)
{
try
{
// await _adapter.ConnectToDeviceAsync(_device);
byte[] senddata = Encoding.UTF8.GetBytes(data);
int start = 0;
while (start < senddata.Length)
{
int chunkLength = Math.Min(20, senddata.Length - start);
byte[] chunk = new byte[chunkLength];
Array.Copy(senddata, start, chunk, 0, chunkLength);
Device.BeginInvokeOnMainThread(async () =>
{
await Task.Delay(300);
await _characteristicsBLE.WriteAsync(chunk);
});
start += 20;
}
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
I have even called the write operation in main thread to avoid any threading issue. But still I get GATT error. I have no clue how to fix this any suggestions?
