The PHASE and many other gaming peripherals support both dongle and Bluetooth connectivity. However, the dongle almost always provides a superior experience. Some key benefits include lower power consumption, a faster polling rate, and an overall smoother gaming experience. 

But have you ever wondered why that’s the case? 
In this devlog, I’ll explain the technical reasons behind this and how our dongle delivers the best gaming experience. 

Polling Rate & Why It Matters 

The polling rate (or refresh rate) refers to how many times per second an input device updates its status to the computer. It’s similar to FPS (frames per second)—the higher the number, the smoother and more responsive the experience. Polling rate applies to all inputs, including buttons and motion sensors. It determines how quickly your mouse detects movement and transmits it to your system. 

Here’s a visual comparison of a high polling rate vs. a low polling rate. You can see that a slower polling rate makes input feel laggy, just like how low FPS results in choppy visuals. 

Is a Higher Polling Rate Always the Solution?

Technically, increasing the polling rate should lead to better responsiveness. However, there’s a bottleneck—the speed of the communication medium. The real question is:

Can the medium transmit data fast enough to support a high polling rate?
For USB and gaming dongles, the answer is yes—they’re fast enough to handle high polling rates. However, Bluetooth isn’t.

Why BLE (Bluetooth low energy) falls short

While Bluetooth is a convenient wireless protocol, it was never designed for high-speed, low-latency data transfer. BLE devices do not communicate continuously over the radio; instead, they operate based on a fixed time interval called the connection interval, during which they exchange data. This approach is excellent for power efficiency, as it allows both devices to turn off their radio and related peripherals to conserve energy. However, it is not ideal for applications requiring rapid data transmission.

The lowest possible connection interval supported by the BLE standard is 7.5ms. This means that even if a BLE mouse’s sensor polls data at 1000Hz, the mouse can only send an update to the computer every 7.5ms, resulting in an effective polling rate of approximately 133Hz. This limitation explains why most BLE mice have a polling rate of 125Hz or lower- also notice how this also introduces a 7.5ms input latency!

How the PHASE dongle overcomes this limitation

Since BLE doesn't support high polling rates, I incorporated a proprietary protocol that utilizes the same 2.4GHz radio as BLE on the MCU. While I won’t go into too much detail due to its proprietary nature, this protocol incorporates a much faster "connection interval," allowing PHASE to transmit sensor data at 1000Hz with just 1ms latency to the PHASE dongle.

The dongle then translates the data into HID reports and sends it over USB to the host device, ensuring a seamless and ultra-responsive experience.

Conclusion

While BLE is perfectly fine for casual gaming and general browsing, I strongly recommend using the dongle for fast-paced, input-sensitive games like Ghost of Tsushima to ensure smooth and responsive gameplay.

That said, BLE does have the advantage of not requiring a USB dongle, making it more convenient for everyday use. Hopefully, in the future, the BLE protocol will introduce a “gaming mode” to improve its performance for high-speed applications.