Shell - Hall Effect Bricklet¶

Simple¶

Download (example-simple.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your Hall Effect Bricklet

# Get current edge count without reset
tinkerforge call hall-effect-bricklet $uid get-edge-count false

Callback¶

Download (example-callback.sh)

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#!/bin/sh
# Connects to localhost:4223 by default, use --host and --port to change this

uid=XYZ # Change XYZ to the UID of your Hall Effect Bricklet

# Handle incoming edge count callbacks
tinkerforge dispatch hall-effect-bricklet $uid edge-count &

# Set period for edge count callback to 0.05s (50ms)
# Note: The edge count callback is only called every 0.05 seconds
#       if the edge count has changed since the last call!
tinkerforge call hall-effect-bricklet $uid set-edge-count-callback-period 50

echo "Press key to exit"; read dummy

kill -- -$$ # Stop callback dispatch in background

Command Structure¶

The common options of the call and dispatch commands are documented here. The specific command structure is shown below.

tinkerforge call hall-effect-bricklet [<option>..] <uid> <function> [<argument>..]¶

Parameters:	<uid> – Type: String <function> – Type: String

The call command is used to call a function of the Hall Effect Bricklet. It can take several options:

• --help shows help for the specific call command and exits
• --list-functions shows a list of known functions of the Hall Effect Bricklet and exits

tinkerforge dispatch hall-effect-bricklet [<option>..] <uid> <callback>¶

Parameters:	<uid> – Type: String <callback> – Type: String

The dispatch command is used to dispatch a callback of the Hall Effect Bricklet. It can take several options:

• --help shows help for the specific dispatch command and exits
• --list-callbacks shows a list of known callbacks of the Hall Effect Bricklet and exits

tinkerforge call hall-effect-bricklet <uid> <function> [<option>..] [<argument>..]¶

Parameters:	<uid> – Type: String <function> – Type: String

The <function> to be called can take different options depending of its kind. All functions can take the following options:

• --help shows help for the specific function and exits

Getter functions can take the following options:

• --execute <command> shell command line to execute for each incoming response (see section about output formatting for details)

Setter functions can take the following options:

• --expect-response requests response and waits for it

The --expect-response option for setter functions allows to detect timeouts and other error conditions calls of setters as well. The device will then send a response for this purpose. If this option is not given for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.

tinkerforge dispatch hall-effect-bricklet <uid> <callback> [<option>..]¶

Parameters:	<uid> – Type: String <callback> – Type: String

The <callback> to be dispatched can take several options:

• --help shows help for the specific callback and exits
• --execute <command> shell command line to execute for each incoming response (see section about output formatting for details)

Basic Functions¶

tinkerforge call hall-effect-bricklet <uid> get-value¶

Output:	value – Type: Bool

Returns true if a magnetic field of 3.5 millitesla or greater is detected.

tinkerforge call hall-effect-bricklet <uid> get-edge-count <reset-counter>¶

Parameters:	<reset-counter> – Type: Bool
Output:	count – Type: Int, Range: [0 to 232 - 1]

Returns the current value of the edge counter. You can configure edge type (rising, falling, both) that is counted with set-edge-count-config.

If you set the reset counter to true, the count is set back to 0 directly after it is read.

Advanced Functions¶

tinkerforge call hall-effect-bricklet <uid> set-edge-count-config <edge-type> <debounce>¶

Parameters:	<edge-type> – Type: Int, Range: See symbols, Default: 0 <debounce> – Type: Int, Unit: 1 ms, Range: [0 to 255], Default: 100
Output:	no output

The edge type parameter configures if rising edges, falling edges or both are counted. Possible edge types are:

• 0 = rising
• 1 = falling
• 2 = both

A magnetic field of 3.5 millitesla or greater causes a falling edge and a magnetic field of 2.5 millitesla or smaller causes a rising edge.

If a magnet comes near the Bricklet the signal goes low (falling edge), if a magnet is removed from the vicinity the signal goes high (rising edge).

Configuring an edge counter resets its value to 0.

If you don't know what any of this means, just leave it at default. The default configuration is very likely OK for you.

The following symbols are available for this function:

For <edge-type>:

• edge-type-rising = 0
• edge-type-falling = 1
• edge-type-both = 2

tinkerforge call hall-effect-bricklet <uid> get-edge-count-config¶

Output:	edge-type – Type: Int, Range: See symbols, Default: 0 debounce – Type: Int, Unit: 1 ms, Range: [0 to 255], Default: 100

Returns the edge type and debounce time as set by set-edge-count-config.

The following symbols are available for this function:

For edge-type:

• edge-type-rising = 0
• edge-type-falling = 1
• edge-type-both = 2

tinkerforge call hall-effect-bricklet <uid> get-identity¶

Output:

uid – Type: String, Length: up to 8 connected-uid – Type: String, Length: up to 8 position – Type: Char, Range: [a to h, z] hardware-version – Type: Int Array, Length: 3 0: major – Type: Int, Range: [0 to 255] 1: minor – Type: Int, Range: [0 to 255] 2: revision – Type: Int, Range: [0 to 255] firmware-version – Type: Int Array, Length: 3 0: major – Type: Int, Range: [0 to 255] 1: minor – Type: Int, Range: [0 to 255] 2: revision – Type: Int, Range: [0 to 255] device-identifier – Type: Int, Range: [0 to 216 - 1]

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', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.

The device identifier numbers can be found here. 

Callback Configuration Functions¶

tinkerforge call hall-effect-bricklet <uid> set-edge-interrupt <edges>¶

Parameters:	<edges> – Type: Int, Range: [0 to 232 - 1], Default: 0
Output:	no output

Sets the number of edges until an interrupt is invoked.

If edges is set to n, an interrupt is invoked for every n-th detected edge.

If edges is set to 0, the interrupt is disabled.

tinkerforge call hall-effect-bricklet <uid> get-edge-interrupt¶

Output:	edges – Type: Int, Range: [0 to 232 - 1], Default: 0

Returns the edges as set by set-edge-interrupt.

tinkerforge call hall-effect-bricklet <uid> set-edge-count-callback-period <period>¶

Parameters:	<period> – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0
Output:	no output

Sets the period with which the edge-count callback is triggered periodically. A value of 0 turns the callback off.

The edge-count callback is only triggered if the edge count has changed since the last triggering.

tinkerforge call hall-effect-bricklet <uid> get-edge-count-callback-period¶

Output:	period – Type: Int, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by set-edge-count-callback-period.

Callbacks¶

Callbacks can be used to receive time critical or recurring data from the device:

tinkerforge dispatch hall-effect-bricklet <uid> example

The available callbacks are described below.

tinkerforge dispatch hall-effect-bricklet <uid> edge-count¶

Output:	count – Type: Int, Range: [0 to 232 - 1] value – Type: Bool

This callback is triggered periodically with the period that is set by set-edge-count-callback-period. The parameters are the current count and the current value (see get-value and get-edge-count).

The edge-count callback is only triggered if the count or value changed since the last triggering.