80 MHz Cortex-M3 with USB and CAN — what this part brings to a control board
The Texas Instruments LM3S5P31-IQC80-C5T is a Stellaris ARM Cortex-M3 32-bit single-core MCU clocked at 80 MHz, with 64 KB Flash and 24 KB SRAM. It carries a full industrial-connectivity set: CANbus, USB, LIN, I²C, SPI, SSI, UART, and a 16-channel 10-bit ADC. The 67 GPIOs and internal oscillator let it handle a mixed-signal control board without an external clock source. Rated -40 to 85°C in a 100-LQFP package, it fits factory automation, motor-drive front-ends, and automotive gateway modules where the Stellaris family was originally specified.
80 MHz — what it means for the bus and the task loop
80 MHz is the core speed for this Cortex-M3. That puts it in the mid-range of the Stellaris 5000 series — fast enough to run a CANopen stack, a USB HID class, and a PID loop on a single core without a scheduler fight. The 24 KB SRAM is tight for a full RTOS heap with large buffers; plan for careful memory partitioning if you are running a TCP/IP stack or a graphical display buffer.