Cortex-M3 core at 24 MHz — what the speed rating means for the BOM line
The STM32F100C8T7B: The 24 MHz ceiling is set by the internal oscillator and PLL; the core's single-cycle multiply and hardware divide mean the throughput in DMIPS is about 30 at 24 MHz, enough for sensor fusion, motor-control loops, or HMI keypads that don't need the full 72 MHz of the mainstream STM32F103.
Memory budget and peripheral set for embedded control
64 KB Flash and 8 KB SRAM are typical for a small control application: a motor-control FOC algorithm with Hall-sensor feedback fits in about 20 KB Flash and 3 KB RAM, leaving headroom for a bootloader and communication stack. The 10-channel 12-bit ADC (1 µs conversion time typical) and dual 12-bit DAC cover analog I/O without external converters. Connectivity includes I²C, SPI, two UART/USART with IrDA and LIN support — enough for a Modbus RTU slave, a sensor bus, and a debug console. The 37 I/O lines in a 48-pin package mean only 11 pins are dedicated to power, ground, and oscillator — high I/O density for the footprint.