DLN-4ME Multi Protocol Master Adapter (with enclosure)

Key Features

• USB to SPI master interface with configurable phase, polarity and frequency (up to 48MHz);
• USB to SPI Flash interface
• USB to I2C master interface with configurable frequency (up to 1MHz);
• USB to UART interface;
• 48 digital I/O pins with debounce filter, open drain functionality and embedded pull-up resistors;
• 8 analog inputs with event-driven interface;
• 4 PWM outputs with configurable frequency and duty cycle;
• 3 Pulse and frequency counters with event-driven interface;
• 1 status LED and 2 user-configurable LED's;
• no hidden fees: API, updates, software and technical support are free;
• USB 2.0 high-speed (480 MHz) interface with Plug-and-Play detection and notification;
• RoHS Compliant

Event-Driven Interface

There are two approaches to monitor user actions (e.g. key presses) or sensor measurements. Your application can either poll for changes or react on events.

Here is an example that will help us understand the difference.

Let us assume that our application must notify a user if a voltage level monitored by the DLN-4M adapter is out of the predefined range.

Our application can poll the DLN-4M adapter periodically to check the digital input value. You would have to decide how frequently you need to poll this input. If you poll it too frequently, you unreasonably waste computer resources and USB bandwidth. If you poll it rarely, you can’t react on the changes in a timely manner.

Another approach is to configure the DLN-4M adapter to notify your application when the voltage level crosses the threshold. You application can perform other tasks instead of continuously polling the device. When the voltage level crosses the threshold, the DLN-4M adapter sends an event with current measurements to your application.

The polling approach wastes computer resources and USB bandwidth, while the event-driven interface facilitates more responsiveness.