STM32F303CCT6 256 KB Flash, STM32 ARM Cortex-M4 Mini System Dev Board

Discontinued RobotDyn SKU: RD-STM32F303CCT6
STM32F303CCT6 256 KB Flash, STM32 ARM Cortex-M4 Mini System Dev Board

Overview

The RobotDyn STM32F303CCT6 Black Pill is a significant step up from the Blue Pill — same form factor and pinout, but with:

For applications with heavy DSP, signal processing, motor control, or anything requiring real floating-point math, the F303 is dramatically faster than the F103. For simple GPIO/sensor tasks, the Blue Pill is still cheaper and sufficient.

Hardware FPU — When It Matters

The Cortex-M4’s FPU executes float operations in 1–2 cycles instead of dozens. Real-world impact:

TaskF103 (M3)F303 (M4 + FPU)
1000 × float multiply~6 ms~50 µs
FFT 256-point~12 ms~0.8 ms
PID with float~80 µs~5 µs

If your code uses float or double, the F303 is ~50–100× faster on math-heavy sections.

Pinout

Same physical layout as the Blue Pill — 40 pins (2 × 20 along the long edges):

5V-tolerant on most pins (check datasheet for exceptions on analog pins).

Programming

Unlike the Blue Pill (Arduino bootloader) variant, this board ships with ST factory firmware and requires an ST-Link V2 programmer (cheap clones are widely available for $3–5) for first upload.

  1. Connect ST-Link to the 4-pin SWD header (3.3V, GND, SWCLK, SWDIO)
  2. In Arduino IDE: install STM32duino core, select Tools → Board → STM32F3 series → Generic F303CCTx
  3. Upload method → STM32CubeProgrammer (SWD)
  4. Upload

Native USB DFU (after first SWD upload)

Once you’ve flashed a sketch that enables USB DFU, future uploads can go over USB without ST-Link.

Common Uses

Documentation