Overview
Full support for Speeduino and rusEFI logs in MegaLogViewer (MLG) binary format.
Supported File Format
- Type: Binary file
- Extension:
.mlg - Source: Logged directly by Speeduino/rusEFI
- Identifier: File begins with
MLVLGheader - Channel count: No fixed limit. Current rusEFI firmware logs over 1,000 channels; these load in UltraLog 2.16.1 and later
No Export Required
Unlike Haltech and ECUMaster, Speeduino and rusEFI log directly to the MLG format. Simply load the .mlg file directly into UltraLog.
Binary Field Types
UltraLog supports all MLG field types:
| Type | Description |
|---|---|
| U08 | Unsigned 8-bit integer |
| S08 | Signed 8-bit integer |
| U16 | Unsigned 16-bit integer |
| S16 | Signed 16-bit integer |
| U32 | Unsigned 32-bit integer |
| S32 | Signed 32-bit integer |
| S64 | Signed 64-bit integer |
| F32 | 32-bit floating point |
Supported Channels
Depends on your Speeduino/rusEFI configuration. Common channels include:
Engine
- RPM
- MAP
- TPS
- VE (Volumetric Efficiency)
Fuel
- AFR / Lambda
- Pulse Width
- Fuel Pressure
Ignition
- Advance
- Dwell
Temperatures
- Coolant
- IAT
Sensors
- O2 Sensor
- Battery Voltage
- Various analog inputs
Timestamp Handling
MLG files include precise timestamps for each record, which UltraLog uses for:
- Time axis display
- Playback synchronization
- Cursor position tracking
Channel names
With field normalization on, these Speeduino names show as one standard name. From the OpenECU Alliance Speeduino MLG Binary adapter v1.2.0.
| Shown as | Unit | Names in the log |
|---|---|---|
| Acceleration Enrichment | % | Accel · AE · Accel Enrich · Correction_AccelEnrich |
| Barometric Correction | % | Correction_Baro |
| EGO Correction | % | EGO Correction · EGO Corr · O2 Correction · Correction_AFR |
| Gamma Enrichment | % | Gamma · Total Enrich · Correction_Total |
| IAT Correction | % | Correction_IAT |
| Knock Retard | ° | Knock Retard |
| Warmup Enrichment | % | WUE · Warmup Enrich · Correction_Warmup |
| Gear Position | gear | Gear |
| Battery Voltage | V | Battery · Batt V · Battery Voltage · Battery V |
| After-Start Enrichment | % | Correction_ASE |
| Engine Protection RPM Limit | rpm | Engine Prot. RPM |
| Fan Duty | % | FAN Duty |
| Flex Fuel Correction | % | Correction_Flex |
| Fuel Temperature Correction | % | Correction_FuelTemp |
| Idle Load | % | Idle Load · IAC · IAC Position · IAC value |
| Idle RPM Delta | rpm | Idle RPM Delta |
| Idle Target RPM | rpm | Idle Target RPM |
| Ignition Load | % | IgnitionLoad |
| Injector Duty (Staged) | % | Duty Cycle (Staging) |
| Engine RPM | rpm | RPM · Engine Speed |
| RPM Rate | rpm/s | rpm/s |
| Throttle Position | % | TPS · Throttle · TPS ADC |
| Throttle Rate | percent/s | TPS DOT |
| VE Table 1 | % | VE1 |
| VE Table 2 | % | VE2 |
| VVT Intake Position | ° | VVT1 Angle |
| VVT Intake Bank 2 Actual | ° | VVT2 Angle |
| VVT Intake Bank 2 Duty | % | VVT2 Duty |
| VVT Intake Bank 2 Target | ° | VVT2 Target Angle |
| VVT Intake Duty | % | VVT1 Duty |
| VVT Intake Target | ° | VVT1 Target Angle |
| Water Injection Duty | % | WMI Duty Cycle |
| Air-Fuel Ratio | AFR | AFR · O2 · AFR Primary |
| AFR Bank 2 | AFR | AFR2 |
| AFR Target | AFR | AFR Target · Target AFR · AFR Tgt |
| Injector Duty Cycle | % | Duty · Injector Duty · Duty Cycle |
| Dwell (Measured) | ms | Dwell (Measured) |
| Engine Protection AFR Limit | AFR | Engine Prot. AFR |
| Ethanol Content | % | Eth % |
| Fuel Load | % | FuelLoad |
| Injector Open Time | ms | Injector Open Time |
| Lambda | λ | Lambda |
| Lambda Target | λ | Lambda Target |
| Injector Pulse Width | ms | PW · Pulse Width · PW1 |
| Pulse Width 2 | ms | PW2 |
| Pulse Width 3 | ms | PW3 |
| Pulse Width 4 | ms | PW4 |
| Pulse Width 5 | ms | PW5 |
| Pulse Width 6 | ms | PW6 |
| Pulse Width 7 | ms | PW7 |
| Pulse Width 8 | ms | PW8 |
| VE | % | VE · VE1 · VE Current · VE (Current) |
| Dwell | ms | Dwell · Dwell Time |
| Ignition Advance | ° | Advance · Spark Advance · Timing · Advance (Current) |
| Ignition Advance Cylinder 1 | ° | Advance 1 |
| Ignition Advance Cylinder 2 | ° | Advance 2 |
| Knock Count | count | Current Knock Events |
| Barometric Pressure | kPa | Baro Pressure |
| Boost Duty | % | Boost Duty · VVT Duty |
| Boost Target | kPa | Boost Target · Target Boost |
| Engine Protection MAP Limit | kPa | Engine Prot. MAP |
| Engine Protection Oil Limit | kPa | Engine Prot. Oil Pressure |
| Exhaust Manifold Pressure | kPa | EMAP |
| Flex Boost Correction | kPa | Boost Flex Adjust |
| Fuel Pressure | psi | Fuel Pressure |
| Manifold Pressure | kPa | MAP · Manifold Pressure |
| MAP Rate | kpa/s | MAP DOT |
| Oil Pressure | psi | Oil Pressure |
| Vehicle Speed | kph | Wheel Speed (kph) |
| Boost Cut Active | Boost cut | |
| Clutch Switch | Clutch | |
| Fan Relay 1 | Fan | |
| Fuel Staging Active | Fuel Staging | |
| Idle Control Active | Idle Control | |
| Knock Detected | Knock Detected | |
| Launch Control Active | Hard Launch | |
| Nitrous Stage 1 Active | Nitrous | |
| Overrun Cut Active | DFCO | |
| Rev Limiter Active | Hard Limiter | |
| ECU Temperature | °C | System Temperature |
| Error Code | code | Error ID |
| Active Error Count | count | Error # |
| Free RAM | bytes | freeRAM · Free RAM |
| Loops Per Second | Hz | loopsPerSecond · Loops · Loops/s |
| Sync Level | count | Sync status |
| Sync Loss Count | count | Sync Loss # |
| Time | s | Time |
| ECU Uptime | s | SecL |
| Coolant Temperature | °C | CLT · Coolant · Coolant Temp |
| Engine Protection Coolant Limit | °C | Engine Prot. CLT |
| Fuel Temperature | °C | Fuel Temp |
| Intake Air Temperature | °C | IAT · Intake Temp · Air Temp |