Saleae Support
HomeDownloadUser ForumContact Us
  • Saleae Support
  • Orders & Shipping
    • Place an Online Order
    • Place a Purchase Order (PO)
    • Get a Quote
    • Check your Order Status
    • Distributors
    • Pricing and Availability
    • Discounts
    • Tax & VAT Exemption
    • Saleae Business Information
    • Shipping Policy
    • Receiving Invoices
    • Sales FAQ
      • What Is Included with the Product?
      • What Accessories Should I Purchase with My Device?
      • Is the Saleae Software Sold Separately?
      • Does Saleae Have a Trade-In or Upgrade Plan?
      • How Can I Find the Current Status of My Order?
      • Part Numbers, ECCN, HS Codes, and Country of Origin
      • Discontinued Products
      • International Customs and Duty Information
      • Does Saleae Offer Demo Units or Units on Loan?
      • When Is My Card Charged?
      • Unable to Ship to PO Box Error
      • Referred a Friend? Email Us!
      • Does Saleae Provide Drop-Shipping Service?
  • Getting Started
    • Setup
    • Configure
    • Record
    • Navigate
    • Measure
    • Trigger
    • Protocols
  • User Guide
    • Product Summary
    • Safety & Warranty
    • Supported Voltages
    • Device Calibration
    • Using Logic
      • Navigating the Software
      • Connecting the Logic Analyzer
      • Logic Accessories
      • Device Settings
      • Capture Modes
      • Navigating Your Data
      • Time Bar Settings
      • Measurements, Timing Markers & Notes
      • Capture & Preset File Management
      • Exporting Data
      • Delete Part of your Capture
      • Analyzers
      • Data Table & Terminal View
      • Color Themes
      • Demo Mode
      • Software Glitch Filter
      • Keyboard Shortcuts
      • Automatic Updates
      • Message Us Directly
  • Software
    • Supported Operating Systems
    • Download
    • Installation
    • Firmware Updates
    • Driver Install
    • Legacy Software
      • Logic 1.x Download (Deprecated)
      • Logic 1.x Installation (Deprecated)
      • Logic 1.x Changelog (Deprecated)
      • Logic 1.x User Guide (Deprecated)
  • Protocol Analyzers
    • Supported Protocols
    • Analyzer User Guides
      • Async Serial Analyzer - User Guide
        • Decode UART
        • Decode RS-232, RS-485, & RS-422
      • SPI Analyzer - User Guide
      • I2C Analyzer - User Guide
      • CAN Analyzer - User Guide
      • Simple Parallel Analyzer - User Guide
      • I2S / PCM Analyzer - User Guide
      • DMX-512 Analyzer - User Guide
      • SMBus Analyzer - User Guide
      • Decode Differential and High Voltage Data
  • Software Extensions
    • Extension Installation
    • Create and Use Extensions
    • High-Level Analyzer (HLA) Extensions
      • Shared High Level Analyzers (HLAs)
    • Measurement Extensions
      • Analog Measurement Extensions
      • Digital Measurement Extensions
    • Extension File Format
    • About Third-Party Extensions
    • Disabling Marketplace Extensions
    • Publish an Extension
    • HLA - Analyzer Frame Format
      • Async Serial - Frame Format
      • I2C - Frame Format
      • SPI - Frame Format
      • CAN - Frame Format
      • Manchester - Frame Format
      • 1-Wire - Frame Format
      • Async RGB LED - Frame Format
      • Simple Parallel - Frame Format
      • LIN - Frame Format
      • I2S - Frame Format
    • API Documentation
  • Automation & Analyzer SDK
    • Automation API - Logic 2
    • Automation API - Legacy Logic 1.x
    • Protocol Analyzer SDK
      • FrameV2 / HLA Support - Analyzer SDK
      • Rename a Custom Analyzer
    • More Information on our SDKs
      • Can I Access Raw Data in Real Time?
      • Migrate Code to the New Analyzer SDK
      • Sharing Custom Low-Level Analyzer (LLA) Code
      • VB.NET Support for Automation
  • Datasheets & Specifications
    • Datasheets
    • Logic Hardware Revisions
    • Logic Dimensions
    • Compliance Documents
  • Troubleshooting
    • Installation Errors
    • The Software Fails to Launch
    • The Software Crashes
    • Logic is Not Detected
    • Getting your Machine ID
    • Getting your Software Crash Logs
    • Getting the Console Output
    • Location of Your Config File
    • Error Message: ReadTimeout
    • The Captured Data Looks Incorrect
    • The Captured Data is Corrupted
    • A Protocol Analyzer Produces Unexpected Results
    • The 'Waiting for Trigger' Window Never Closes
    • Device USB VID and PID Information
    • Error Message: Out of Memory Exception Was Thrown
    • PC Performance Issues with Logic
    • Data Export Is Not Working
    • Error Message: A device was found, but the software was unable to access it
    • Trouble Downloading the Latest Software
    • Logic Does Not Connect over USB 3.0
    • Why Am I Seeing Spikes in the Digital Capture?
    • Logic Interferes with My Circuit Operation
    • The Add Analyzer Menu Is Not Displaying
    • Other Drivers Interfere with Logic's Operation
    • The Maximum Sample Rate is Not Selectable
    • The Digital and Analog Recording on the Same Channel Appear Different
    • Advanced USB Debugging for USB 3.0 Users with Linux Kernels 3.3 and Older
    • Saving or Loading Anything Crashes the Software
    • Error Message: The application was unable to start correctly (0xc0000005)
    • Memory Usage with Triggered Captures
    • The Cabinet File disk1.cab has an Invalid Digital Signature (Logic 1.x)
    • Software Crashes with Virtual Desktops
    • Pre-Trigger Buffer is Incomplete
    • Linux Shared Memory Crash
    • Missing Files: api-ms-win-crt-runtime-l1-1-0.dll or msvcp140.dll
    • Known Issues on OS X
    • A Measurement Appears Incorrect
    • All Known Issues
    • USB 3.0 Cable Customer Notice (2017)
    • Warning Message: Logic Pro is running as a USB 2.0 device
    • Software Issues with Encryption Products
    • Linux Permission Requirements for Logic Software
    • My Rise Time and Fall Time Measurements Seem Incorrect
    • The Analog Waveform Loads Very Slowly after Capture Is Complete
    • Input Channels are Missing
    • Exported MATLAB File Does Not Open
    • Saleae Logic LED Blinks Red
    • Crashes Caused by macOS Mojave (10.14)
    • Troubleshooting Signal Crosstalk
    • Error Message: DeviceSetupFailure
    • Error Message: Unable to detect WebGL and Other GPU Issues
    • Warning Message: Unsupported Version
    • Error Function: Device2::SetupDevice
    • Warning Message: Possible USB Host Controller Problem Detected
    • Error Message: StartCommandError
    • Logic 2 Error Messages
    • PC Detection Test
    • CentOS Compatibility Issues
    • Error Message: Failed to Load Extension
    • CSV Export is Slow
    • Set an Analyzer Starting Point in your Capture
    • Logic 2 is Consuming Disk Space
    • Connection Conflicts with USB Debuggers
    • PC Restart Causes Logic to Disconnect
    • HLA Fails to Display Special Characters
    • Data Table Shows Incorrect Values
    • Error Message: Failed to Load Custom Analyzer
    • Error Message: Capture Stopped
    • Error Loading Marketplace Extensions
    • Error: Capture stopped because backlog data exceeded 90%
    • This Analyzer's Native Export is Not Supported in Logic 2
    • Mouse Scrolling Issues
    • Error: A device was found, but it was removed before initialization completed
    • Error: An unknown error occurred during device connection
    • Visual Studio Error: Failed to Launch Debug Adapter
    • VS Code Fails to Launch Python Automation API Script
    • Analog Waveforms Do Not Appear on Linux
    • Reinstall USB Host Controller Drivers
  • FAQ
    • Technical FAQ
      • System Requirements for Saleae Products
      • What Is the Normal Behavior of the LED?
      • What Is the Difference between Logic/Logic16 (Gen1) and Logic 8/Pro 8/Pro 16 (Gen2)?
      • Recommended USB 3.0 Host Controller Cards
      • Device Settings Configuration Tips
      • What Is the Worst Case Channel to Channel Skew?
      • What is Asynchronous Sampling?
      • Which Saleae Products Can Decode 4-Bit Parallel LCD Communications?
      • How Can I Compare Two Clock Signals for Synchronization and Drift?
      • Converting I2S/PCM Captures into Audio
      • My Capture Shows an Uneven Duty Cycle
      • Can I Create or Edit .logicdata Files?
      • Can Saleae Logic Run on ARM / Apple Processors?
      • What Annotations Are Supported?
      • Time & Memory Saving Tools
      • How Can I Record Power Consumption?
      • Moving Logic to Its Own Host Controller
      • How Long Does It Take to Save a File?
      • XMonad on Linux Causes Issues
      • What Is the Maximum Bandwidth of Logic?
      • How Long Can I Record Data?
      • Can I Export Protocol Results Between Timing Markers?
      • Can I Generate an Analog Graph from Digital Data?
      • Time Measurement Error
      • Can These Products Replace an Oscilloscope?
      • Can I Use Multiple Logics on a Single PC?
      • Native Windowing Features Are Not Working Such as Snap or Gestures
      • Opening .logicdata Capture Files
      • How to Choose the Right Logic Analyzer for You
      • Saleae Open Source Support
      • How to Trigger the End of a Capture Instead of the Start
      • Using the Hardware with USB Extension Cables, Through Virtual Machines, or Ethernet Extenders
      • Are the Ground Pins Required for Each Input Used?
      • Can Saleae Products Output Data?
      • Resolution of the Analog Inputs
      • What Sampling Rate Should I Use?
      • Can I Share Data Captures with Others?
      • Binary Export Format (Digital) - Logic 1.x
      • MATLAB Data Export Format - Legacy Logic 1.x
      • Recording Multiple Protocols at the Same Time
      • Changing the Display Radix (Base)
      • Which Logic Analyzer Should I Get?
      • How to View and Debug Firmware Variables, State, and Function Calls
      • Using Saleae Logic Devices with Third-Party Pattern Generators
      • Can Logic Operate with a Full-Speed USB Isolator?
      • Which Saleae Devices Support Analog Recording?
      • How to Manage Protocol Analyzers when Using the Socket API
      • How to Export Serial Protocol Results to a Raw Binary File
      • How to Trigger On a Pulse with No Maximum Time Limit - Logic 1.x
      • Finding Your USB 3.0 Host Controller Information
      • Logic Reports Different USB Current Requirements
      • Is It Possible to Adjust the Logic Thresholds for the Digital Inputs?
      • Why Does Channel 0 Use a Black Wire?
      • Software Shows Multiple Logic Analyzers Attached
      • Are the Input Channels Isolated from Each Other?
      • Are There Feature Differences in the Software when Different Logic Analyzers Are Used?
      • Packet Level Decoding Support in the Analyzer SDK
      • What Higher-Level Protocol Analysis Features Are Available?
      • Support for USB 3.0 and USB 3.1
      • How Can I Compare Signals from Different Captures?
      • Do the Saleae Logic Analyzers Support Trigger Out?
      • Why is the Length of my Capture Incorrect?
      • The Options Button is Missing
      • Can I Change the Voltage Range of the Analog Inputs?
      • How Does the ASCII Radix Display Characters?
      • Do I Have a USB 3.0 Port?
      • What Is the Best Way to Compare Similar Sequences of Protocol Data?
      • Which Version of the Software Should I Use?
      • Import Custom Low Level Analyzer
      • OSX Analyzer SDK Xcode Setup
      • Can Custom Analyzers Process Analog Channels?
      • Automating Long Overnight Captures
      • What Options Are There to Export Multiple Protocol Analyzer Results into the Same File?
      • Do the Saleae Devices Support AC Coupling?
      • Suggestions for Capturing Multiple Instances of a Triggered Event Automatically
      • How Many Protocol Analyzers Can Be Used at Once?
      • Is It Possible to Run the Saleae Software on a PC without SSE2 Instructions?
      • Is It Possible to Import Data into the Logic Software?
      • How Do I Convert Exported CSV Analog Data in Voltages?
      • Is There Cross-Platform Support for the SaleaeSocketApi C# Project
      • Why Does Logic Get Warm?
      • Binary Export Format (Analog) - Logic 1.x
      • Electrical Isolation Suggestions
      • FCC and CE Testing Recommendations
      • 'Save Capture' and 'Export Data' is Disabled in the Software
      • File Format Description for Exporting Protocol Analyzer Results
      • Is There a Newer Version of the Software Available?
      • Is There a Way to Change the Window Resolution?
      • How Can I Extract Recorded Data Using Socket API?
      • Does the Software Support Windows 10 Tablets or Windows RT Tablets?
      • Standalone Software Information
      • Does the Saleae Software Support the Original Logic and Logic 16?
      • Timing Markers Disappear When I Start a New Capture
      • What Sample Rate Settings Are Available? Can I Sample at a Slower Rate?
      • How Do I Differentiate Data in the Export File when Duplicate Analyzers Are Used?
      • Running Multiple Versions of the Software
      • Test Clip Differences - Gen 1 & Gen 2
      • USB-C Cable Recommendations
      • Is My Capture Data Private?
      • Ethernet Connectivity Suggestions
      • Binary Export Format - Logic 2
      • Viewing I2C Addresses as 8-bit
      • Can I use Python Packages in my Custom Extension?
      • Are the Inputs Synchronously Sampled or Sweep Sampled?
      • Is Logic Affected by the Log4j Exploit?
      • Connecting Remotely with SSH
      • Is Silent Installation Supported?
      • Is the .sal File Format Documented?
      • Export Data via Socket API
      • Running Logic in a CI Environment on Windows with the SYSTEM Account
    • General FAQ
      • How Do I Get More Help on an Issue That's Outside the Scope of Saleae Support?
      • How to Identify Each Saleae Device
      • License for the Saleae Logic Software, SDKs, and APIs
      • How Do You Pronounce Saleae?
      • How to Create Project Content for Saleae
  • Returns & Warranty
    • Submit a Warranty Claim
  • Community
    • Ideas & Feedback
    • User Forum
    • Community Projects
    • Community Created Accessories
    • Community Shared Analyzers
  • Tutorials
    • Oscilloscope Tutorial
    • Logic Analyzer Tutorial
    • Learning Portal
      • Digital Protocols
        • Learn Asynchronous Serial
        • Learn I2C - Inter-Integrated Circuit
        • Learn SPI - Serial Peripheral Interface
        • Learn CAN – Controller Area Network
        • Digital MultipleX (DMX512)
        • Manchester
        • 1-Wire
        • Learn I2S / PCM
        • Management Data Input/Output (MDIO)
        • BiSS C
        • HDMI Consumer Electronics Control (CEC)
        • PS/2 Keyboard/Mouse
        • Universal Serial Bus (USB) 2.0
        • Single-Wire Interface (SWI)
        • Simple Parallel
        • Local Interconnect Network (LIN)
        • Joint Test Action Group (JTAG)
      • Common Acronyms and Definitions
      • What is a Glitch?
      • What is RAM? Why Does Logic Use it?
      • What is a Display Radix?
      • What is Data Bandwidth? Can I Reduce this in Logic?
    • Example Projects
      • STM32 Nucleo Board - Digital Signals
      • STM32 Nucleo Board - Analog Signals
      • STM32 Nucleo Board - Analyzing UART
      • STM32 Nucleo Board - Analyzing SPI
      • STM32 Nucleo Board - Analyzing I2C
Powered by GitBook
On this page
  • Why Does Logic Use RAM to Store Capture Data?
  • How Much RAM is Needed?
  • Analog Data RAM Usage
  • Digital Data RAM Usage
  • What If my RAM is Not Enough?
Edit on GitHub
Export as PDF
  1. Tutorials
  2. Learning Portal

What is RAM? Why Does Logic Use it?

PCs typically contain and use two hardware memory types. That is the hard disk and RAM. Because of their inherent properties, they are used for different purposes.

The hard disk is where your programs and files are stored. This memory type will contain much more memory space than RAM, can keep its contents even while powered-off, and is much slower to access its data than RAM. Examples of hard disks include hard disk drives (using a spinning disk), solid-state drives, and USB flash drives.

On the other hand, RAM (short for Random Access Memory) is reserved for programs that are currently running. RAM will contain much less memory space when compared to hard disks, and loses its contents when powered-off. Its advantage is extremely fast access to its data, which is important for currently running programs to run quickly and smoothly.

Why Does Logic Use RAM to Store Capture Data?

If hard disks contain much more memory space than RAM, then it would make sense for Logic to utilize the hard disk when capturing data, right? Well, not exactly...

Logic captures data at such a fast rate that it requires nearly instant access to PC memory in order to save the incoming data stream properly. If we direct the Logic software to stream its data directly to the hard disk during a data capture, the incoming data would simply overflow and have no where to go since typical hard disk speeds cannot support the speed of incoming data from Logic.

For this reason, Logic currently cannot support continuous capture directly to a file stored on the hard disk. Instead, the data captures reside in RAM until it is saved to the disk via Options -> Save Capture, or when the associated capture tab is closed at the bottom of the software.

How Much RAM is Needed?

The amount of RAM needed for a data capture is dependent on five factors:

  • Number of channels

  • Type of channel (analog or digital)

  • Sampling rate

  • Duration of the capture

  • Toggles/sec of incoming digital data

The software will estimate the RAM/memory usage on the device settings popover.

Analog Data RAM Usage

  • RAM usage for analog data depends on (1) the number of analog channels, (2) the analog sampling rate, and (3) the duration of the capture.

  • Analog data is sampled and stored at a fixed rate. Therefore, its RAM usage will increase if any of the 3 properties above increase.

Digital Data RAM Usage

  • RAM usage for digital data depends on (1) the number of digital channels, (2) toggles/sec of incoming data, and (3) the duration of the capture.

  • Contrary to analog captures, digital captures will only store data in RAM when a toggle occurs on the digital channel. For this reason, it is typically recommended to sample at the highest digital sampling rate since it will not use any more memory than using a slower digital sampling rate (assuming the same data is captured). Due to this property, keep in mind that capturing very fast data with a large amount of toggles/sec will consume more RAM than digital data that is mostly inactive, keeping the number of digital channels and duration the same.

What If my RAM is Not Enough?

Besides modifying the capture settings or buying more RAM, our Socket API automation script allows users to break extremely long captures into a series of shorter captures that are saved to the hard disk. You can read more about how to implement this below.

PreviousWhat is a Glitch?NextWhat is a Display Radix?

Last updated 3 years ago

Automating Long Overnight Captures