> For the complete documentation index, see [llms.txt](https://docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verifone.com/adk-os-platform/readme/user-interface-and-application-control.md). # User interface and application control Review the VOS3 UI stack, media support, Multi-Application Controller capabilities, and system control panel operations. VOS3 provides HTML-based UI services and a system-level application controller. Use this page to review UI capabilities, how the Multi-Application Controller manages application runtime behavior, and the system control panels available to operators and engineers. ## User interface functions | **UI Function** | **Support** | | ------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | HTML | | | ECMA6 (JavaScript) | | | Images | | | Animated images | | | Video playback |

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| | Audio playback | | | Barcode reading | Supported through the UI stack where applicable | | Framebuffer | No direct framebuffer access for applications | ## Multi-Application Control (MAC) functions MAC manages application launch, switching, and access to shared system UI. | **Function** | **Support** | | ------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | System status bar | | | System settings panel | | | Application launch | | | Application switching | | | CP application embedding | | ## Runtime model Applications run under MAC control. MAC provides a consistent way to launch applications, expose system UI, and coordinate multi-application behavior on the device. This is the expected runtime model for headed VOS3 deployments. ## MAC Desktop The MAC Desktop is the entry point for launching applications and accessing system control panels. To open the MAC Desktop: * Press **1-5-9** on keypad devices * Long-press the **system status bar** on touch-only devices The MAC Desktop opens automatically on boot when no auto-launch application is configured, or when the device is in a tampered state. Selecting **Control Panel** from the MAC Desktop opens the MAC Control Panel Desktop, which provides access to all system settings panels. {% hint style="info" %} MAC Desktop and control panel access can be protected by a password policy. See [VOS3 Password Management](/adk-os-platform/readme/vos3-password-management.md) for details. {% endhint %} *** ## System control panels ### System Information Displays device identification and resource information: * **HW info** — model name, part number, hardware ID, serial number * **SW info** — OS and ADK version, UI identifier string in the format `x` * **Memory info** — available and free RAM, available and free flash ### Date & Time Management Allows operators to: * Set system date, time, and timezone * Configure the 24-hour automatic reboot time {% hint style="info" %} The device has a built-in real-time clock (RTC) set during manufacturing. The RTC cannot be changed during production use. The system time is independent of the RTC but can only vary from it within a **±7-day window**. {% endhint %} Automatic reboot is triggered when a system time change crosses the configured 24h reboot time and the last reboot occurred less than 24 hours ago. Changing the 24h reboot time itself requires a device reboot. ### Settings Allows operators to adjust: * **Display** — brightness and display settings * **Audio** — volume and audio output settings * **Keyboard** — keypad settings ### Transfer Logs Transfers system and application logs to a connected USB stick for offline analysis. ### Application List Lists all applications installed on the device and all running system daemons, together with their current running status. ### Communication Settings Configures and controls communication interfaces including LAN, Wi-Fi, Bluetooth, Serial-PPP, and USB gadgets. New features in VOS3: * Display of the Wi-Fi country code * Diagnostics for serial lines * BLE Beacons Setup * BLE Pairing Events ### Diagnostic Provides hardware test tools for field and development use: | **Tool** | **Function** | | ------------ | -------------------------------------------------------------------------------------------------------------- | | Display | Cycles through Black/White and RGB color patterns | | Keyboard | Tests physical keypad presses; auto-closes after a period of inactivity | | Card | MSR — track reading status, length, error code; Smart Card — slot status; Contactless — reader characteristics | | Buzzer/Audio | Set and test buzzer beep; test audio file playback | | LED | Enable and disable device LEDs where present | | Touch | Test touch panel coordinates and signature capture; option to save a signature file on the device | | SD Card | Read SD card presence and content (on supported devices) | | Battery | Backup battery (coin cell) — status and voltage; portable battery info (portable devices only) | ### Log Control Configures system and application logging behavior: * **Channels** — enable or disable individual log channels, set destination (Syslog, Console, or both), and set the log mask (level filter) * **Syslog log level** — global minimum level for syslog output * **Syslog output** — Serial, File, UDP, or USB * **Output parameters** * File: number of files in the rolling set and maximum file size per file * Serial: serial port number * UDP: destination IP address and port {% hint style="warning" %} Enabling logs is intended for troubleshooting only. Leaving logs enabled long-term reduces system performance and increases flash wear. Disable logs when they are no longer needed. {% endhint %} ### Power Allows operators to: * Reboot the device * Shut down the device * Enter sleep mode (on supported devices) ### Security Control Provides key management and security functions. **Keys** | **Operation** | **Description** | | ---------------------------- | --------------------------------------------------------------- | | Warrantied Key Status | Lists loaded system warrantied keys with key info | | Payment Key Status | Lists loaded customer payment keys with key info | | Load Warrantied Keys | Loads warrantied keys from a connected key loading device (KLD) | | Load Payment Keys | Loads VRK payment key JSON files from USB stick or SD card | | Write VRK Certificate to USB | Transfers the VRK certificate to an attached USB stick | **Tamper** | **Operation** | **Description** | | ------------- | ------------------------------------------------------------------------------------ | | Tamper Status | Shows the current tamper condition | | Tamper Log | Shows the tamper event history | | Clear Tamper | Resets the tamper condition for further analysis — does **not** de-tamper the device | **Security Identification** Displays firmware and hardware version information: * Model name and hardware ID * VOS3 PCI security version * Secure processor boot loader version (SPBL) * Secure processor firmware version (SPFW) * Application processor firmware version (APFW) **Date and Time** *(security-controlled)* * View current RTC and system time * Set Secure RTC date and time — not available on PROD devices * Synchronize RTC time to system time **MIB** * View MIB info * Load MIB **Password Manager** * Change user passwords * List all passwords defined by the loaded Password Policy file ### Software Management | **Operation** | **Description** | | ------------------ | -------------------------------------------------------------------------------- | | Download USB | Browse and install DL files from a USB stick or SD card | | Download Netloader | Install DL files from a connected host PC using the Netloader protocol | | Download ZonTalk | Install DL files from a connected host PC using the ZonTalk serial protocol | | Install Result | Displays the result of the latest installation | | Software List | Lists all installed SW packages with version and details; allows bundle deletion | ### VHQ Settings | **Operation** | **Description** | | ------------- | ---------------------------------------- | | Versions | Displays the installed VHQ agent version | | Heartbeat | Starts a VHQ heartbeat | | Reset Agent | Resets the VHQ agent (requires reboot) | ### VCL Settings Displays VCL status information. --- # Agent Instructions This documentation is published with GitBook. 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