A professional, easy-to-use Arduino library for the Onsemi FUSB302 USB Type-C Port Controller. This library provides comprehensive support for USB Type-C cable detection, orientation sensing, VBUS voltage monitoring, and USB Power Delivery protocol communication.
- USB Type-C Detection: Automatic cable orientation detection (normal/flipped)
- Power Delivery Support: Full USB PD message transmission and reception
- PD Hard Reset: Send hard reset messages to force PD state machine reset
- VBUS Monitoring: Accurate voltage measurement (0-22V range)
- Multiple SOP Types: Support for SOP, SOP', and SOP'' messaging
- Flexible Configuration: CC pin configuration for source and sink modes
- I2C Communication: Simple I2C interface (typically at 0x22)
- Comprehensive Examples: Detailed example sketches included
- Professional Documentation: Extensive inline documentation and Doxygen support
- Error Handling: Robust error checking and reporting
- Maker-Friendly: Designed with ease of use and learning in mind
| Device | Description |
|---|---|
| FUSB302B | Programmable USB Type-C Controller with PD (Default SNK) |
| FUSB302T | Programmable USB Type-C Controller with PD (Default SRC) |
- Open Arduino IDE
- Go to Tools → Manage Libraries
- Search for "SitronLabs FUSB302"
- Click Install
Add to your platformio.ini:
lib_deps =
sitronlabs/SitronLabs_FUSB302_Arduino_Library- Download the latest release from GitHub
- Extract the ZIP file
- Copy the
SitronLabs_Onsemi_FUSB302_Arduino_Libraryfolder to your Arduinolibrariesdirectory - Restart Arduino IDE
#include <Wire.h>
#include <fusb302.h>
fusb302 usb_controller;
void setup() {
Serial.begin(115200);
Wire.begin();
/* Initialize FUSB302 at I2C address 0x22 */
usb_controller.setup(Wire, 0x22);
if (!usb_controller.detect()) {
Serial.println("FUSB302 not found!");
while(1);
}
usb_controller.power_set(true);
Serial.println("FUSB302 ready!");
}
void loop() {
/* Read CC pins to detect cable orientation */
enum usb_typec_cc_status cc1, cc2;
usb_controller.cc_measure(cc1, cc2);
if (cc1 > USB_TYPEC_CC_STATUS_OPEN && cc2 == USB_TYPEC_CC_STATUS_OPEN) {
Serial.println("Cable: Normal orientation");
}
else if (cc1 == USB_TYPEC_CC_STATUS_OPEN && cc2 > USB_TYPEC_CC_STATUS_OPEN) {
Serial.println("Cable: Flipped orientation");
}
delay(1000);
}void loop() {
float voltage;
if (usb_controller.vbus_measure(voltage) == 0) {
Serial.print("VBUS: ");
Serial.print(voltage, 2);
Serial.println(" V");
}
delay(1000);
}| FUSB302 Pin | Arduino Pin | Description |
|---|---|---|
| VDD | 3.3V | Power supply (3.3V only!) |
| GND | GND | Ground |
| SDA | SDA | I2C data line (4.7kΩ pull-up) |
| SCL | SCL | I2C clock line (4.7kΩ pull-up) |
| CC1 | USB-C CC1 | Configuration channel 1 |
| CC2 | USB-C CC2 | Configuration channel 2 |
| VBUS | USB-C VBUS | USB power line (up to 20V) |
| INT | Digital pin | Interrupt (optional) |
- Voltage: FUSB302 operates at 3.3V only. Use level shifters with 5V Arduino boards.
- Pull-ups: I2C lines require 4.7kΩ pull-up resistors to 3.3V.
- VBUS: Can measure 0-22V directly. Use voltage divider for higher voltages.
| Device | Default Address |
|---|---|
| FUSB302BMPX | 0x22 |
| FUSB302TMPX | 0x22 or 0x23 (configurable) |
/* Setup I2C communication */
int setup(TwoWire &i2c_library, uint8_t i2c_address);
/* Detect if chip is present */
bool detect();
/* Software reset */
int reset();
/* Power control */
int power_set(bool on);/* Measure CC pin status */
int cc_measure(enum usb_typec_cc_status &cc1, enum usb_typec_cc_status &cc2);
/* Set cable orientation */
int cc_orientation_set(enum usb_typec_cc_orientation orientation);
/* Configure CC pull resistors */
int cc_pull_down();
int cc_pull_up(enum usb_typec_cc_status status);/* Measure VBUS voltage */
int vbus_measure(float &voltage);/* PD initialization */
int pd_reset();
int pd_autogoodcrc_set(bool enabled);
int pd_autoretry_set(int retries);
/* Message handling */
int pd_message_receive(struct usb_pd_message &msg);
int pd_message_send(const struct usb_pd_message msg);
/* Buffer management */
int pd_rx_flush();
int pd_tx_flush();struct usb_pd_message {
enum usb_pd_sop_type sop_type; /* SOP, SOP', or SOP'' */
uint16_t header; /* Message header */
uint32_t objects[7]; /* Data objects */
uint8_t object_count; /* Number of objects (0-7) */
};All methods return an integer error code:
0: Success1: Success with data (forpd_message_receive())- Negative values: Error codes
Common error codes:
-EIO: I2C communication error-EINVAL: Invalid parameter-EBUSY: Device busy-ENODEV: Device not found
- Check power supply is 3.3V (not 5V!)
- Verify I2C wiring (SDA, SCL, GND)
- Confirm I2C address (use I2C scanner)
- Check pull-up resistors on I2C lines (4.7kΩ)
- Ensure chip has proper power (check VDD pin)
- Verify CC1 and CC2 are connected to USB-C connector
- Test with a different USB-C cable
- Ensure cable is fully inserted
- Check for proper CC pin termination
- Reset PD logic:
usb_controller.pd_reset() - Verify cable orientation is set correctly
- Confirm connected device supports USB PD
- Enable auto-GoodCRC:
usb_controller.pd_autogoodcrc_set(true) - Check that VBUS is present
- Verify VBUS connection to chip
- Ensure measurement range (0-22V)
- Test with known voltage source
This library is released under the MIT License. See LICENSE.txt for details.
For support, please:
- Check the Issues page
- Join our Discord community for live support and discussion
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