Configuration

This guide covers all configuration options available for the AS5047U driver.

Compile-Time Configuration

Kconfig Options

If your project uses Kconfig (e.g., ESP-IDF), the following options are available:

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AS5047U Configuration
    AS5047U_FRAME_FORMAT (16/24/32-bit)
    AS5047U_CRC_RETRIES (default: 0)

Configuration Header

You can also configure the driver by editing inc/as5047u_config.hpp:

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namespace AS5047U_CFG {
    // Default SPI frame format
    inline constexpr FrameFormat DEFAULT_FRAME_FORMAT = FrameFormat::SPI_24;
    
    // Number of CRC retries (0 = no retry)
    inline constexpr uint8_t CRC_RETRIES = 3;
}

Runtime Configuration

SPI Frame Format

The driver supports three SPI frame formats:

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// 16-bit frames (no CRC, highest throughput)
as5047u::AS5047U encoder(spi, FrameFormat::SPI_16);

// 24-bit frames (includes 8-bit CRC, recommended)
as5047u::AS5047U encoder(spi, FrameFormat::SPI_24);

// 32-bit frames (includes 8-bit CRC + 8-bit pad for daisy-chain)
as5047u::AS5047U encoder(spi, FrameFormat::SPI_32);

Recommendation: Use SPI_24 for most applications - it provides CRC protection with good throughput.

Change Frame Format at Runtime 

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encoder.SetFrameFormat(FrameFormat::SPI_24);

Sensor Configuration

Zero Position

Set the zero reference position (soft offset):

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// Set zero position to current angle
uint16_t current_angle = encoder.GetAngle();
encoder.SetZeroPosition(current_angle);

// Or set a specific value (0-16383)
encoder.SetZeroPosition(8192);  // 180 degrees

Rotation Direction 

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// Clockwise rotation yields increasing angle (default)
encoder.SetDirection(true);

// Counter-clockwise rotation yields increasing angle
encoder.SetDirection(false);

Dynamic Angle Error Compensation (DAEC)

DAEC provides low-latency angle correction for high-speed applications:

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// Enable DAEC (recommended for high-speed applications)
encoder.SetDynamicAngleCompensation(true);

// Disable DAEC (use raw angle)
encoder.SetDynamicAngleCompensation(false);

Adaptive Filter (DFS™)

The Dynamic Filter System adaptively filters noise:

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// Enable adaptive filter
encoder.SetAdaptiveFilter(true);

// Set filter parameters (K_min, K_max)
// K_min: minimum filter strength (0-15)
// K_max: maximum filter strength (0-15)
encoder.SetFilterParameters(2, 3);

Angle Output Source

Select which angle is used for outputs (ABI, UVW, PWM):

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// Use compensated angle (with DAEC)
encoder.SetAngleOutputSource(AS5047U_REG::SETTINGS2::AngleOutputSource::Compensated);

// Use raw angle (without DAEC)
encoder.SetAngleOutputSource(AS5047U_REG::SETTINGS2::AngleOutputSource::Raw);

Output Configuration

ABI (Incremental Encoder) Output

Configure incremental encoder outputs (A, B, I):

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// Set resolution (10-14 bits)
encoder.SetABIResolution(12);  // 12-bit = 4096 PPR

// Set index pulse length (1 or 3 LSB periods)
encoder.SetIndexPulseLength(1);

// Enable ABI output
encoder.ConfigureInterface(true, false, false);  // ABI only

UVW (Commutation) Output

Configure 3-phase commutation outputs:

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// Set number of pole pairs (1-7)
encoder.SetUVWPolePairs(5);  // 5 pole pairs

// Enable UVW output
encoder.ConfigureInterface(false, true, false);  // UVW only

PWM Output

Configure PWM-encoded angle output:

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// Enable PWM output
// PWM appears on W pin if ABI enabled, or I pin if UVW enabled
encoder.ConfigureInterface(true, false, true);  // ABI + PWM

Combined Outputs 

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// Enable both ABI and UVW (PWM not available in this mode)
encoder.ConfigureInterface(true, true, false);

// Enable ABI with PWM on W pin
encoder.ConfigureInterface(true, false, true);

Advanced Configuration

Hysteresis

Set incremental output hysteresis to reduce jitter:

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// Set hysteresis level
encoder.SetHysteresis(AS5047U_REG::SETTINGS3::Hysteresis::LSB_1);

High-Temperature Mode

Enable 150°C operation mode:

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encoder.Set150CTemperatureMode(true);

OTP Programming

Program current settings into OTP (One-Time Programmable) memory for permanent configuration:

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// Configure all settings first
encoder.SetZeroPosition(0);
encoder.SetDirection(true);
encoder.SetABIResolution(12);
// ... other settings

// Program to OTP (one-time operation, cannot be undone)
bool success = encoder.ProgramOTP();
if (success) {
    // Settings are now permanent
}

Warning: OTP programming is irreversible. Make sure all settings are correct before programming.

CRC Retry Configuration

Configure automatic retry on CRC errors:

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// Read with automatic retry (3 attempts)
uint16_t angle = encoder.GetAngle(3);

// Or set default retries in config
// AS5047U_CFG::CRC_RETRIES = 3;

Default Values

Option Default Description
DEFAULT_FRAME_FORMAT SPI_16 SPI frame format
CRC_RETRIES 0 Number of CRC retries
Zero Position 0 Zero reference angle
Direction true (CW) Rotation direction
DAEC enabled Dynamic angle compensation
Adaptive Filter enabled DFS adaptive filtering
ABI Resolution 14-bit Incremental output resolution
UVW Pole Pairs 1 Commutation pole pairs

For High-Speed Motor Control 

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encoder.SetDynamicAngleCompensation(true);  // Enable DAEC
encoder.SetAdaptiveFilter(true);            // Enable DFS
encoder.SetFilterParameters(2, 3);         // Moderate filtering
encoder.SetABIResolution(12);              // 4096 PPR
encoder.ConfigureInterface(true, false, false);  // ABI output

For Low-Noise Applications 

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encoder.SetAdaptiveFilter(true);
encoder.SetFilterParameters(3, 5);          // Stronger filtering
encoder.SetHysteresis(AS5047U_REG::SETTINGS3::Hysteresis::LSB_2);

For Basic Angle Reading 

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// Use default settings, just read angle
uint16_t angle = encoder.GetAngle();

Next Steps

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