An experimental library for bridging USB-OTG Host stack on Espressif ESP32 (S Series). This project is based on sample code on ESP-IDF Programming Guide. Developed for Arduino framework on espressif32 (4.4.0) on PlatformIO.
This 🎥 Video demo how it works in 🕹📡 simpleTx_esp32
- Create daemon and driver tasks like the official doc said
- Fetch endpoints from interfaces, pick one EP-IN to interrupt later
- Get HID Report Descriptor, print it to serial. No fancy parser implemented
- Repeatly, request report packet from EP-IN
HID Report Descriptor is not parsed due to calibration is needed and will do the job in real life application. User can dump the HEXes from serial ouptut, and decode it via an online parser.
Only tested on NodeMCU-32-S2-Kit, an ESP32-S2 WiFi Development Board, with ESP-12K Module. An USB Type-A female connector is connected to USB_D- (GPIO19) & USB_D+ (GPIO20) for USB Hosting. All other S series boards should work with those exposeing USB data pins.
Define the global variables before void Setup()
void hid_report_descriptor_cb(usb_transfer_t *transfer);
void hid_report_cb(usb_transfer_t *transfer);
UsbHostHidBridge hidBridge;Put these lines inside void Setup()
hidBridge.setOnHidReportDescriptorReceived( hid_report_descriptor_cb );
hidBridge.setOnReportReceived( hid_report_cb );
hidBridge.begin();Define a callback function to decode the raw HID_REPORT_DESCRIPTOR packet
void hid_report_descriptor_cb(usb_transfer_t *transfer) {
for(int i=0; i < transfer->actual_num_bytes; i++) {
if (i == USB_SETUP_PACKET_SIZE) {
Serial.printf("\n\n>>> Goto https://eleccelerator.com/usbdescreqparser/ \n");
Serial.printf(">>> Copy & paste below HEX and parser as... USB HID Report Descriptor\n\n");
}
Serial.printf("%02X ", transfer->data_buffer[i]);
}
}Define a callback function to decode the raw GET_REPORT packet
void hid_report_cb(usb_transfer_t *transfer) {
unsigned char *const data = (unsigned char *const)(transfer->data_buffer);
// print data_buffer in binary format
for (int i=0; i<transfer->actual_num_bytes && i<11; i++) { // prints first 11 bytes only!!!
for (int b=0; b<8; b++) Serial.printf("%d", (data[i] & (1 << b)) >> b );
Serial.printf(" ");
}
Serial.printf("\n");
}After Build, Run, & Monitoring, and plug an HID device (e.g. a PS4 gamepad) to USB-A connector. The serial output on IDE should shows the bit stream from ypur HID device.
Have fun!
MIT