Note
This Bricklet is currently in the prototype stage and the software/hardware as well as the documentation is in an incomplete state.
This is the description of the C# API bindings for the Heart Rate Bricklet. General information and technical specifications for the Heart Rate Bricklet are summarized in its hardware description.
An installation guide for the C# API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 | using Tinkerforge;
class Example
{
private static string HOST = "localhost";
private static int PORT = 4223;
private static string UID = "abc"; // Change to your UID
static void Main()
{
IPConnection ipcon = new Tinkerforge.IPConnection(); // Create IP connection
BrickletHeartRate hr = new Tinkerforge.BrickletHeartRate(UID, ipcon); // Create device object
ipcon.Connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Get current heart rate (in beats per minute)
int hrate = hr.GetHeartRate();;
System.Console.WriteLine("Heart Rate(bpm): " + hrate);
System.Console.WriteLine("");
System.Console.WriteLine("Press key to exit");
System.Console.ReadLine();
ipcon.Disconnect();
}
}
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 | using Tinkerforge;
class Example
{
private static string HOST = "localhost";
private static int PORT = 4223;
private static string UID = "abc"; // Change to your UID
// Callback function for heart rate callback
static void HeartRateCB(BrickletHeartRate sender, int hrate)
{
System.Console.WriteLine("Heart Rate(bpm): " + hrate);
System.Console.WriteLine("");
}
static void Main()
{
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletHeartRate hr = new BrickletHeartRate(UID, ipcon); // Create device object
ipcon.Connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Set Period for heart rate callback to 1s (1000ms)
// Note: The heart rate callback is only called every second if the
// heart rate has changed since the last call!
hr.SetHeartRateCallbackPeriod(1000);
// Register heart rate callback to function HeartRateCB
hr.HeartRate += HeartRateCB;
System.Console.WriteLine("Press key to exit");
System.Console.ReadLine();
ipcon.Disconnect();
}
}
|
Download (ExampleThreshold.cs)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 | using Tinkerforge;
class Example
{
private static string HOST = "localhost";
private static int PORT = 4223;
private static string UID = "abc"; // Change to your UID
// Callback for color threshold reached
static void ReachedCB(BrickletHeartRate sender, int hrate)
{
System.Console.WriteLine("Heart Rate(bpm): " + hrate);
System.Console.WriteLine("");
}
static void Main()
{
IPConnection ipcon = new IPConnection(); // Create IP connection
BrickletHeartRate hr = new BrickletHeartRate(UID, ipcon); // Create device object
ipcon.Connect(HOST, PORT); // Connect to brickd
// Don't use device before ipcon is connected
// Get threshold callbacks with a debounce time of 10 seconds (10000ms)
hr.SetDebouncePeriod(10000);
// Register threshold reached callback to function ReachedCB
hr.HeartRateReached += ReachedCB;
// Configure threshold for heart rate values,
// Heart Rate : greater than 70 beats per minute
hr.SetHeartRateCallbackThreshold('>', 50, 70);
System.Console.WriteLine("Press key to exit");
System.Console.ReadLine();
ipcon.Disconnect();
}
}
|
Generally, every method of the C# bindings that returns a value can throw a Tinkerforge.TimeoutException. This exception gets thrown if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody plugs the device out). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.
Since C# does not support multiple return values directly, we use the out keyword to return multiple values from a method.
The namespace for all Brick/Bricklet bindings and the IPConnection is Tinkerforge.*.
All methods listed below are thread-safe.
Creates an object with the unique device ID uid:
BrickletHeartRate heartRate = new BrickletHeartRate("YOUR_DEVICE_UID", ipcon);
This object can then be used after the IP Connection is connected (see examples above).
Returns the current heart rate measured.
If you want to get the heart rate periodically, it is recommended to use the callback HeartRate and set the period with SetHeartRateCallbackPeriod().
Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.
Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.
For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by SetResponseExpected(). For setter functions it is disabled by default and can be enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.
See SetResponseExpected() for the list of function ID constants available for this function.
Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled and callbacks it is always disabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.
The following function ID constants are available for this function:
Changes the response expected flag for all setter and callback configuration functions of this device at once.
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c' or 'd'.
The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.
Sets the period in ms with which the HeartRate callback is triggered periodically. A value of 0 turns the callback off.
HeartRate is only triggered if the heart rate has changed since the last triggering.
The default value is 0.
Returns the period as set by SetHeartRateCallbackPeriod().
Sets the thresholds for the HeartRateReached callback.
The following options are possible:
Option | Description |
---|---|
'x' | Callback is turned off |
'o' | Callback is triggered when the heart rate is outside the min and max values |
'i' | Callback is triggered when the heart rate is inside the min and max values |
'<' | Callback is triggered when the heart rate is smaller than the min value (max is ignored) |
'>' | Callback is triggered when the heart rate is greater than the min value (max is ignored) |
The default value is ('x', 0, 0).
The following constants are available for this function:
Returns the threshold as set by SetHeartRateCallbackThreshold().
The following constants are available for this function:
Sets the period in ms with which the threshold callback
is triggered, if the threshold
keeps being reached.
The default value is 100.
Returns the debounce period as set by SetDebouncePeriod().
Enables the BeatStateChanged callback.
Disables the BeatStateChanged callback.
Returns true if the BeatStateChanged callback is enabled.
Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by appending your callback handler to the corresponding event:
void Callback(BrickletHeartRate sender, int value)
{
System.Console.WriteLine("Value: " + value);
}
heartRate.ExampleCallback += Callback;
The available events are described below.
Note
Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.
This callback is triggered periodically with the period that is set by SetHeartRateCallbackPeriod(). The parameter is the heart rate of the sensor.
HeartRate is only triggered if the heart rate has changed since the last triggering.
This callback is triggered when the threshold as set by SetHeartRateCallbackThreshold() is reached. The parameter is the heart rate of the sensor.
If the threshold keeps being reached, the callback is triggered periodically with the period as set by SetDebouncePeriod().
This callback provides the current heart beat state.It is called every time a heart beat is detected. The state can either be
The following constants are available for this function:
This constant is used to identify a Heart Rate Bricklet.
The GetIdentity() function and the EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.