The Ultimate Serial Port

"Your Debug Buddy"
from Mystic Engineering

Debug Buddy


The Ultimate Serial Port is your Debug Buddy, hacking tool, and hands-on problem solver.


  • USB serial port: Serial with selectable level shifters (outputs RS232, 5V, or3.3V levels), null modem, gender changer
  • Level Shifters: Two programmable six channel level shifters, 3.3V to 5V or 5V to 3.3V
  • Debug LEDS: Eight LEDs drivable directly from microcontroller or IC, light when 3.3V or 5V is applied
  • Clock source: Thirteen square waves from 24Mhz to 366Hz

Use it to:

  • Connect your PC or Mac via USB to various microcontrollers physical serial ports, include the Arduino, Raspberry Pi, Beagle, STM32F4 Discovery, ARM, PIC, AVR, ... for outputting printf style debugging messages, running serial debug monitors, ...
  • Shift signal levels between different logic families, (3.3V->5V and 5V->3.3V)
  • Monitor output signals with debugging LEDs
  • Generate a square wave for clocking an microcontroller or IC, debugging input captures/timers, etc

Replace all these items with one convenient board!

USB Serial Port Adafruit 954 3.3V
Serial Port
RS232 to TTL/3.3V

Null Modem Gender Changer

Level Shifters Clock Generator Debug LEDs


Debug Buddy v1.4
(assembled and tested)

$34.99 Temporarily Out of Stock
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