# Silent Sentry **URL:** \ **Category:** Jacdac\ **Created:** [November 2, 2026, 9:40pm UTC](https://forum.makecode.com/t/silent-sentry/46887 "2026-11-02T21:40:31Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Scruff](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.makecode.com/scruff/32/34627_2.png) [@Scruff](https://forum.makecode.com/u/Scruff)\ **Post date:** [November 2, 2026, 9:40pm UTC](https://forum.makecode.com/t/silent-sentry/46887/1 "2026-11-02T21:40:31Z")
> **[Silent Sentry](https://makecode.microbit.org/S06332-57757-92454-90813)** > > Made with ❤️ in Microsoft MakeCode for micro:bit. Microsoft Jacdac is an open source hardware and software platform designed to bring a plug and play experience to low cost physical computing. Developed by Microsoft Research, it simplifies how micro controllers like the BBC micro:bit connect to and communicate with peripheral devices such as sensors, sliders and actuators. Core Features: Plug and Play Simplicity: Devices and their services are discovered dynamically as soon as they are plugged into the system. There is no need to hunt down individual, device specific libraries. Daisy Chaining Architecture: Modules can be seamlessly chained together to allow near limitless hardware expansion using unified cables. Hardware Standardization: It enforces strict hardware specifications, including standardized PCB based edge connectors, reversible cables and unified current ratings. Six MakeCode handheld consoles with at least one Jacdac port are available on the market today: Kittenbot’s Newbit Arcade Shield – one Jacdac port ICShopping’s Game:bit Arcade Shield – two Jacdac ports ELECFREAKS’ micro:bit Arcade Shield – one Jacdac port Forward Education’s CodeCTRL Shield – two Jacdac ports TomatoCube’s MakeCode Arcade Display Shield for micro:bit – one Jacdac port ELECFREAKS’ micro:bit Arcade Pro – one Jacdac port This project requires the following parts: 1 x Handheld console (from the list above) 1 x Jacdac cable 1 x Human Infrared Sensor Note: The Jacdac cable and sensor used in this project were obtained from ELECFREAKS. Project Overview & Assembly: The Silent Sentry silently detects and records motion in any selected area. The Human Infrared Sensor features two LEGO mounting holes that can be attached to a LEGO Technic structure using two Technic pins with short friction ridges (Item No. 2780). Connect the Human Infrared Sensor to the handheld console using the Jacdac cable. ![Jacdac Motion Sensor](https://us1.discourse-cdn.com/flex020/uploads/makecode/original/3X/8/b/8bcea0967ef60bd35d395979927a3fc47548489d.png) ``` Jacdac Motion Sensor ``` Operation: Once the software is downloaded onto the handheld console, it operates as follows: The Menu Page: Pressing Button [A] opens the Test Mode page. Pressing Button [B] opens the Sentry Mode page. Test Mode: The Test Mode page displays the number of times motion has been detected. Every time motion is detected, a short tone plays and sensor detection pauses for 5 seconds. This ensures a single trigger from the Jacdac sensor increments the counter only once, rather than dozens of times per second while the sensor signal remains active. Pressing the MENU button at any time returns you to the Menu page. Sentry Mode: The Sentry Mode page also displays the number of times motion has been detected. Pressing Button [UP] turns the screen black to hide the display. While the screen is hidden, the counter continues to increment in the background whenever motion is detected. Pressing Button [DOWN] reveals the Sentry Mode screen with the updated total. Pressing the MENU button at any time returns you to the Menu page.