The (also seen as Unisoc SCI USB2Serial ) is a proprietary USB-to-serial bridge interface used by Spreadtrum (now Unisoc) mobile chipsets. It enables low-level communication between a PC and a Spreadtrum-based device (feature phone, smartphone, IoT module) over USB. Unlike standard UART adapters (CP2102, FTDI), this driver presents a Diagnostic Port (DIAG) and often a Debug Port (SPRD DEBUG) for:
// lsusb -v output (simplified) idVendor 0x1782 Spreadtrum idProduct 0x4d00 bDeviceClass 0x02 (Communications) bDeviceSubClass 0x00 bDeviceProtocol 0x00 spreadtrum sci usb2serial ok
: Allows a Windows computer to recognize a Spreadtrum-powered device when connected in "Download Mode" or "SPD Boot Mode". Identification : In Windows Device Manager , a successful connection often appears under the "Ports (COM & LPT)" section as "SCI USB2Serial" "SCI Android USB2Serial" Hardware ID : Commonly identified by the vendor and product ID USB\VID_1782&PID_4D00 Common Use Cases Firmware Flashing : Essential for tools like UpgradeDownload or ResearchDownload to write new software to the device. The (also seen as Unisoc SCI USB2Serial )
Power and mode