| Reference Section | Information Available |
| Introduction | SDK scope and supported device classes, package contents, nomenclature (device, host, user), and host requirements, including the certificates needed for TLS and secure WebSocket connections. |
| How to Set Up the SDK | Steps to download the SDK package, add the library to your project, and build and run the MTUSDKDemo sample app. |
| Core API | Static entry points for finding and creating devices (getDeviceList, createDevice, and device-specific factory functions), API version lookup, and MQTT broker, topic, QoS, client ID, and certificate settings for network-connected devices. |
| IDevice (Payment Functions) | The primary device object. Start and cancel transactions; request PIN, PAN, signature, and user selections; send the processor’s ARPC with sendAuthorization; send Mifare Classic, DESFire, and Plus NFC tag commands; get the device’s capability, control, configuration, and connection objects; and subscribe to device events. |
| IDeviceCapabilities | Read-only properties for checking hardware support before you call a feature: display, PIN pad, signature capture, battery-backed clock, MSR power saver, SRED, and the bitmask of supported payment methods. |
| IDeviceControl | Direct device control: open and close the connection, reset the device, send raw, extended, and synchronous commands, show messages, images, and QR codes, run the barcode reader, NFC pass-through, and NFC card emulation, set the card latch and LEDs, capture personal info entry, and manage External Accessory discovery and notifications. |
| ConnectionInfo | .Connection parameters for a device: device type, connection type, the address format for each transport (IP, TLS, Bluetooth LE, WebSocket, serial), and certificate information for TLS and secure WebSocket connections. |
| DeviceInformation | Device identity properties (model, name, and serial number) and the initializer for a DeviceInfo object. |
| iDeviceConfiguration | Configuration and maintenance: read and write device settings by OID, retrieve device info, key info, and challenge tokens, send and retrieve files and images, set the idle-screen image, update keys, and update main, wireless, and Bluetooth LE firmware. Asynchronous operations report through IConfigurationCallback. |
| ConfigurationInfo | The object for building OID-based configuration requests: configuration type (device settings or device information), the OID-and-value payload, and initializers that build it from an ASN.1 OID path. |
| Data Classes | Objects passed to and returned from the API: IData (string or byte payload), IResult, ITransaction (amount, currency, payment methods, QuickChip, tip, and Apple VAS settings), CertificateInfo, and parsers for barcode, NFC, R-APDU, and personal info entry data. |
| IEventSubscriber Delegates | The OnEvent callback, which delivers nearly all device output (card data, transaction status, ARQC requests, PIN blocks, NFC and barcode data) after you register with subscribeAll. |
| IConfigurationCallback Delegates | Callbacks for asynchronous configuration operations: OnProgress for percent complete, OnResult for completion status and data, and OnCalculateMAC for requests that must carry a MAC. |
| MTUSDKDelegate Delegates | iOS host-level callbacks: onDeviceList returns devices found through Bluetooth LE and External Accessory discovery, and didSystemUpdateState reports changes in Bluetooth, network, and server connectivity. |
| Enumerations | Enumerated values used across the SDK: device and connection types, connection and transaction states, event types, payment methods, status codes, NFC events and modes, info types, system states, and Apple VAS modes. |
| Appendices | Worked examples: an API walkthrough with sample code for the main interfaces, and a step-by-step EMV transaction flow. |