Definition: Mod_log_firstbyte refers to a term in computer engineering used for calculating the first byte of data in an input stream, such as a serial or USB cable, to be read by a receiver device before it starts reading the next bytes. It's used in hardware programming and often found in Linux kernels for reading from USB devices or other network interfaces. Detailed definition: Mod_log_firstbyte is a term in computer engineering that refers to calculating the first byte of data (such as serial numbers) that needs to be read by an input stream before it starts reading the next bytes. It's typically used in hardware programming and Linux kernel for reading from USB devices or other network interfaces, especially when dealing with serial communication protocols like Serial2 or UART.