The upgraded version uses the latest firmware -2020-12-R1 ONE is an open source 2.4 GHZ wireless development platform suitable for Bluetooth experiments. Based on the powerful LPC175XARM -M3 microcontroller and full-speed USB 2.0, the ONE is a great way to develop custom Class 1 comparable Bluetooth devices. The difference between and other Bluetooth development platforms is that it is not only to send and receive 2.4GHZ signals, but can also run in monitoring mode to monitor Bluetooth traffic in real time. This mode of operation has existed in low-cost WIFI modules for many years and has seen countless applications in research, development, and security audits, but until now, the Bluetooth standard had no such solution. Additionally, since it is a completely open source platform (software and hardware), the schematics and code are readily available for all your needs. feature: 2.4 GHz mit and receive. mit power and receive sensitivity are comparable to Class 1 Bluetooth devices. Standard Debug Connector (10-pin 50 JTAG) In-System Programming (ISP) Serial Connector Expansion Connector intended for use with communications or other uses Six indicator lights included 2.4 GHz antenna Note: In order to open the schematic and board design files in package you need to download KiCad, an open source electronic design automation software package. Material: plastic colour: Black Package Contents: 1 x Analytical equipment Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.