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TLV493D 3D Magnetic Field Sensor Module

Nim wrapper for the TLV493D 3-axis magnetic field sensor.

The TLV493D is a low-power 3D magnetic sensor that can measure magnetic field strength in X, Y, and Z axes. It's useful for position sensing, proximity detection, joystick applications, and rotary encoding.

Features:

3-axis magnetic field measurement
Temperature sensor
Low power consumption with multiple power modes
I2C interface only
Configurable measurement rates
Magnetic field resolution: 0.098 mT per LSB

Example:

import nimphea
import nimphea/dev/tlv493d

var sensor: Tlv493dI2C
var config: Tlv493dConfig

# Configure I2C transport
config.transport_config.address = TLV493D_ADDRESS1
config.transport_config.periph = I2C_PERIPH_1
config.transport_config.speed = I2C_400KHZ
config.transport_config.scl = seed.GetPin(11)  # PB8
config.transport_config.sda = seed.GetPin(12)  # PB9

if sensor.init(config) == TLV493D_OK:
  while true:
    sensor.updateData()
    let x = sensor.getX()        # in mT
    let y = sensor.getY()        # in mT
    let z = sensor.getZ()        # in mT
    let temp = sensor.getTemp()  # in °C
    let amount = sensor.getAmount()    # total field strength
    let azimuth = sensor.getAzimuth()  # angle in XY plane
    # Use sensor data...

Imports

nimphea, i2c

Types

Tlv493dAccessMode {.importcpp: "daisy::Tlv493d<daisy::Tlv493dI2CTransport>::AccessMode_e", size: 4.} = enum POWERDOWNMODE = 0, ## Power down mode (1000ms delay) FASTMODE = 1, ## Fast mode (no delay) LOWPOWERMODE = 2, ## Low power mode (10ms delay) ULTRALOWPOWERMODE = 3, ## Ultra low power mode (100ms delay) MASTERCONTROLLEDMODE = 4 ## Master controlled mode (10ms delay): Power and measurement access modes Source Edit
Tlv493dConfig {.importcpp: "daisy::Tlv493dI2C::Config", bycopy.} = object transport_config* {.importcpp: "transport_config".}: Tlv493dI2CTransportConfig: TLV493D device configuration Source Edit
Tlv493dI2C {.importcpp: "daisy::Tlv493dI2C", bycopy.} = object: TLV493D sensor with I2C transport Source Edit
Tlv493dI2CTransport {.importcpp: "daisy::Tlv493dI2CTransport", bycopy.} = object: I2C transport for TLV493D Source Edit
Tlv493dI2CTransportConfig {.importcpp: "daisy::Tlv493dI2CTransport::Config", bycopy.} = object periph* {.importcpp: "periph".}: I2CPeripheral speed* {.importcpp: "speed".}: I2CSpeed scl* {.importcpp: "scl".}: Pin sda* {.importcpp: "sda".}: Pin address* {.importcpp: "address".}: uint8: I2C transport configuration Source Edit
Tlv493dResult {.importcpp: "daisy::Tlv493d<daisy::Tlv493dI2CTransport>::Result", size: 4.} = enum TLV493D_OK = 0, ## Success TLV493D_ERR = 1 ## Error: Operation result Source Edit

Consts

TLV493D_ADDRESS1 = 0x5E'u8: I2C address 1 Source Edit
TLV493D_ADDRESS2 = 0x1F'u8: I2C address 2 Source Edit
TLV493D_B_MULT = 0.098'f32: Magnetic field LSB multiplier (mT) Source Edit

Procs

proc enableTemp(this: var Tlv493dI2C; enable: bool) {. importcpp: "#.EnableTemp(#)", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Enable or disable temperature measurements

Parameters:

enable - true to enable temperature sensor, false to disable

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proc getAmount(this: var Tlv493dI2C): cfloat {.importcpp: "#.GetAmount()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Get the total magnetic field strength

Calculates sqrt(x² + y² + z²)

Returns: Total magnetic field magnitude in mT
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proc getAzimuth(this: var Tlv493dI2C): cfloat {.importcpp: "#.GetAzimuth()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Get the azimuth angle in the XY plane

Calculates arctan(y/x)

Returns: Azimuth angle in radians
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proc getMeasurementDelay(this: var Tlv493dI2C): uint16 {. importcpp: "#.GetMeasurementDelay()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Get the current measurement delay in milliseconds

The delay depends on the current access mode.

Returns: Measurement delay in ms
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proc getPolar(this: var Tlv493dI2C): cfloat {.importcpp: "#.GetPolar()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Get the polar angle

Calculates arctan(z/sqrt(x² + y²))

Returns: Polar angle in radians
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proc getTemp(this: var Tlv493dI2C): cfloat {.importcpp: "#.GetTemp()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Get the temperature reading

Returns: Temperature in degrees Celsius
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proc getX(this: var Tlv493dI2C): cfloat {.importcpp: "#.GetX()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Get the X-axis magnetic field strength

Returns: X-axis magnetic field in mT (millitesla)
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proc getY(this: var Tlv493dI2C): cfloat {.importcpp: "#.GetY()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Get the Y-axis magnetic field strength

Returns: Y-axis magnetic field in mT (millitesla)
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proc getZ(this: var Tlv493dI2C): cfloat {.importcpp: "#.GetZ()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Get the Z-axis magnetic field strength

Returns: Z-axis magnetic field in mT (millitesla)
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proc init(this: var Tlv493dI2C; config: Tlv493dConfig): Tlv493dResult {. importcpp: "#.Init(#)", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Initialize the TLV493D sensor

Parameters:

config - Configuration struct with transport settings

Returns: TLV493D_OK on success, TLV493D_ERR on failure
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proc initTlv493dConfig(): Tlv493dConfig {.constructor, importcpp: "daisy::Tlv493dI2C::Config(@)", header: "dev/tlv493d.h".}: Initialize device config with defaults Source Edit
proc initTlv493dI2CTransportConfig(): Tlv493dI2CTransportConfig {.constructor, importcpp: "daisy::Tlv493dI2CTransport::Config(@)", header: "dev/tlv493d.h".}: Initialize I2C transport config with defaults Source Edit
proc setAccessMode(this: var Tlv493dI2C; mode: Tlv493dAccessMode) {. importcpp: "#.SetAccessMode(#)", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Set the power/measurement access mode

Parameters:

mode - Access mode (power down, fast, low power, ultra low power, or master controlled)

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proc setInterrupt(this: var Tlv493dI2C; enable: bool) {. importcpp: "#.SetInterrupt(#)", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Enable or disable interrupts

Parameters:

enable - true to enable interrupts, false to disable

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proc updateData(this: var Tlv493dI2C) {.importcpp: "#.UpdateData()", header: "dev/tlv493d.h", ...raises: [], tags: [], forbids: [].}: Update sensor readings

Call this regularly to fetch new magnetic field and temperature data. Respects the measurement delay based on the current access mode.
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