tolerance and supports direct NOR and NAND flash memory media through a flash wear leveling product called LevelX. Embedded graphical user interface GUIX is the embedded graphical user interface (GUI) for ThreadX. GUIX provides a 2D runtime system (environment) for embedded applications running ThreadX. GUIX supports multiple display devices with a variety of screen resolutions and color depths. Many predefined graphical widgets are available. A Windows WYSIWYG host tool called GUIX Studio automatically generates C code for GUIX to execute at runtime. Embedded networking NetX Duo is the embedded TCP/IP system for ThreadX. NetX Duo supports both IPv4 and IPv6 networking along with protocols such as ARP, Auto IP, DHCP, DNS, DNS-SD, FTP, HTTP, ICMP, IGMP, mDNS, POP3, PPP, PPPoE, RARP, TFTP, SNTP, SMTP, SNMP, and TELNET. IP layer network security is provided by IPsec. TCP and UDP socket layer security is provided by TLS and DTLS, respectively. IoT Cloud protocol support includes CoAP, MQTT, and LWM2M. NetX Duo also supports Thread and 6LoWPAN. In 2017, ThreadX and NetX Duo became a Thread Certified Product. Embedded USB USBX is the embedded Universal Serial Bus (USB) system for ThreadX. USBX supports both host and device. Host controller support includes EHCI, OHCI, and proprietary USB host controllers. USBX also supports OTG. USBX class support includes Audio, Asix, CDC/ACM, CDC/ECM, DFU, GSER, HID, PIMA, Printer, Prolific, RNDIS, and Storage. Safety certification ThreadX (and FileX and NetX Duo) have been precertified by SGS-TÜV Saar to the following safety standards: IEC 61508 SIL 4, IEC 62304 Class C, ISO 26262 ASIL D, and EN 50128 SW-SIL 4. ThreadX (and FileX and NetX Duo) have been precertified by UL to the following safety standards: UL/IEC 60730, UL/IEC 60335, UL 1998 ThreadX has also been certified to DO-178 standards by various military and aerospace companies. It is supported by popular Transport Layer Security (SSL/TLS) libraries such as wolfSSL. Packaging As of 2017, ThreadX is packaged as part of X-Ware IoT Platform in full source code and with no runtime royalty payment. Products using it Some high-profile products using ThreadX range from small wearable devices, to Hewlett-Packard printers, and even NASA’s Deep Impact space probe. The Raspberry Pi line of single-board computers runs ThreadX as a binary blob on the graphics processing unit (GPU). This controls initial booting, which in turn is used to boot secondary operating systems such as Linux, and continues to operate in a more