# Meet Your Joulescope JS320 The JS320 arrives in a carry case:  Unzip the carry case to find the JS320 instrument and accessories:  Your Joulescope JS320 purchase includes: - Joulescope JS320 instrument with factory calibration - Binding Post Front Panel, already installed - 5’ USB 2.0 A to C cable - USB A to C adapter (not shown above) - GPIO cable assembly - 2 mm Allen wrench, for optionally swapping the front panel (not shown above) - Quick Start Guide - Factory calibration certificate (not shown above) - Joulescope sticker - Carry case You will need to provide: - A host computer running one of the [supported platforms](https://docs.joulescope.com/en/getting_started/install_ui.md#supported-platforms). Most computers manufactured within the last five years should work. The computer requires an available USB 2.0 port, at least 500 MB of hard drive / solid state drive storage space, and 1 GB of available RAM. - Suitable cable(s) to connect the Joulescope JS320’s binding posts to your system, often the power source and device under test. - Optional BNC cable for connecting trigger to other equipment. You need an internet connection to download the free software. The front side of the JS320 has the connectors that connect to your system:  Your JS320 measures the voltage across the Voltage + and Voltage – binding posts. Your JS320 measures the current flowing through the Current + to the Current – binding posts. If you have a power source and target device, connect the positive side through the current binding posts. You can then connect the voltage signals across either your power source or your target device. For more connection examples, see [Section 6](https://docs.joulescope.com/en/products/js320/guide/connect.md#js320-how-to-connect-your-joulescope). The Sensor Status indicator is off when your JS320 is powered off or inactive. Slow flashing red indicates that the instrument is ready, but the current flow is not yet enabled. Solid green indicates that current measurement is enabled. Fast flashing red indicates that the soft fuse is engaged. The backside of Joulescope has the host USB connector, status LED, GPIO connector, and trigger connector:  Use the provided USB cable to connect the USB host computer connector to your host computer. If your computer only has USB C ports, use the provided adapter. The Controller Status indicator is off when the JS320 is not connected to the host computer, or the host computer has not yet activated the JS320 over USB. Microsoft Windows computers activate devices immediately when connected while macOS and Linux do not activate the device until the Joulescope software attempts to use the device. Solid blue indicates that the JS320 is activated. Solid green indicates that the JS320 device is running normally. The GPIO connector provides four general-purpose inputs and two general-purpose outputs. See [Section 9](https://docs.joulescope.com/en/products/js320/guide/gpio.md#js320-gpi-gpo) for details. The BNC Trigger connector provides either a Trigger Out or a Trigger In. This Trigger allows the JS320 to synchronize data collection with other equipment.