DL950 Acquisition Application Programming Interface

This high-speed data acquisition system includes software (DL950ACQAPI.dll) that provides an application programming interface (API) for obtaining waveform data being acquired by the DL950 series. 

API Overview

The API is provided as a dynamic link library (DLL). The API can be used by linking user applications with this DLL.
The API supports two acquisition modes: free run and trigger. The API supports connections to multiple DL950s but does not support multi-unit synchronization (/C50 option).

(1) Free run mode
Free run mode is used to acquire data from the start to the end of waveform acquisition.
Zoom waveform display is not possible on the DL950 during waveform acquisition in free run mode.
Waveform acquisition specifications in free run mode
Maximum data rate: 320 MB/s (10 MS/s×16ch) for 10Gbit Ethernet connection
Maximum data rate: 6.4 MB/s (200 kS/s×16ch) for 1Gbit Ethernet/USB connection
Maximum waveform acquisition time: 10 days (maximum operation time guaranteed for this API)

(2) Trigger mode
Trigger mode is used to acquire waveform using triggers. There are two trigger modes available with the API:
(i) Synchronous mode in which the DL950 acquires waveforms synchronously with the PC.
(ii) Asynchronous mode in which the DL950 acquires waveforms asynchronously with the PC.
Note that the API does not support the following features.

  • Waveform acquisition in roll mode (the DL950 itself supports waveform acquisition in roll mode, but the API does not support waveform acquisition while the DL950 is acquiring waveforms in roll mode)
  • DL950 trigger mode set to Single N
  • Waveform acquisition using dual capture
  • Real-time recording (SSD and flash acquisition) (/ST1, /ST2 option)
  • Recorder mode



This software can be used to perform the following functions. For details, see User’s Manual.

  • Initializing the API
  • Connecting and disconnecting from measuring instruments
  • Setting parameters
  • Getting waveform data


Software structure

This software package contains the following items.

  • DL950ACQAPI User’s Manual
  • API files(see below)
File name Content
DL950ACQAPI.dll ACQAPI library
DL950ACQAPI64.dll ACQAPI Library 64-bit Version
DL950ACQAPI.lib ACQAPI Import Library for C++
DL950ACQAPI.h Function Declaration Header File for C++
DL950ACQAPINet.dll Free Run API Library for .NET
tmctl.dll Communication Library
tmctl64.dll Communication Library 64-bit Version


Applicable Model

DL950 (Applicable DL950 firmware version is 1.20 or later.)


System requirements


A PC running the English or Japanese version of Windows 10 (32 bit or 64 bit)
Note that when waveform acquisition in free run mode is performed using this software,
data is saved in a specified buffer. See User’s Manual for more details.

Development Environment

Visual Studio 2017 or later, .NET Framework 4.7 or later

System requirements for running user programs

When using 10Gbit Ethernet connection

  • CPU
    Desktop PC
    Intel Core i7-1165G7 or later, 4 cores(8 threads)or more, 4.7 GHz or faster
  • Memory
    16 GB or more
  • SSD
    512 GB or more(M.2 slot SSD recommended, read/write performance 3 GB/s or better)

When using 1Gbit Ethernet or USB connection

  • CPU
    Intel Core i5-10210U or later, 4 cores(8 threads)or more, 4.2 GHz or faster
  • Memory
    8 GB or more
  • SSD
    256 GB or more SSD(read/write performance 400 MB/s or better)
Date Version Contents
Feb 26, 2024 Fixed some minor bugs
Jun 17, 2022 Added Trigger mode
Dec 17, 2021 New release

Product Overviews


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