esp-idf/examples/peripherals/usb/host/cdc/cdc_acm_host/README.md

| Supported Targets | ESP32-S2 | ESP32-S3 |
| ----------------- | -------- | -------- |

# USB CDC-ACM Host Driver Example

(See the README.md file in the upper level 'examples' directory for more information about examples.)

This example shows how to use the CDC-ACM Host Driver to allow an ESP chip to communicate with a USB CDC-ACM device.

## How to use example

### Hardware Required

Two ESP boards that have USB-OTG supported. One will act as USB host and the other as USB device.  
Connect USB_D+, USB_D-, GND and +5V signals of USB host to USB device.

#### Pin Assignment

See common pin assignments for USB Device examples from [upper level](../../../README.md#common-pin-assignments).

### Build and Flash

1. Build and flash [tusb_serial_device example](../../../device/tusb_serial_device) to USB device board.
2. Build this project and flash it to the USB host board, then run monitor tool to view serial output:

```bash
idf.py -p PORT flash monitor
```

(Replace PORT with the name of the serial port to use.)

(To exit the serial monitor, type ``Ctrl-]``.)

See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.

### Running with dual USB CDC device
USB CDC device example [tusb_serial_device example](../../../device/tusb_serial_device)
can be configured to act as dual CDC device.

In the device example project, enter command `idf.py menuconfig` and set Component config->TinyUSB Stack->Communication Device Class (CDC)->CDC channel Count to `2`.

This settings also changes device's PID, so `EXAMPLE_USB_DEVICE_PID` in [usb-cdc.c](./main/usb-cdc.c) must be changed to `0x4002`.


## Example Output

After the flashing you should see the output at idf monitor:

```
...
I (256) USB-CDC: USB Host installed
I (256) USB-CDC: Opening CDC ACM device 0x303A:0x4001
...
Device descriptor is printed here
...
I (1666) USB-CDC: Data received
I (1666) USB-CDC: 0x3ffc4c20   41 54 0d                                          |AT.|
I (2666) USB-CDC: Data received
I (2666) USB-CDC: 0x3ffc4c20   41 54 2b 47 53 4e 0d                              |AT+GSN.|
I (3666) USB-CDC: Setting up line coding
I (3666) USB-CDC: Line Get: Rate: 115200, Stop bits: 0, Parity: 0, Databits: 8
I (3666) USB-CDC: Line Set: Rate: 9600, Stop bits: 1, Parity: 1, Databits: 7
I (3666) USB-CDC: Line Get: Rate: 9600, Stop bits: 1, Parity: 1, Databits: 7
I (3676) Example finished successfully!
...

```
usb: Add USB host CDC-ACM class driver 2021-07-16 04:01:15 -04:00			`\| Supported Targets \| ESP32-S2 \| ESP32-S3 \|`
			`\| ----------------- \| -------- \| -------- \|`

			`# USB CDC-ACM Host Driver Example`

			`(See the README.md file in the upper level 'examples' directory for more information about examples.)`

			`This example shows how to use the CDC-ACM Host Driver to allow an ESP chip to communicate with a USB CDC-ACM device.`

			`## How to use example`

			`### Hardware Required`

			`Two ESP boards that have USB-OTG supported. One will act as USB host and the other as USB device.`
			`Connect USB_D+, USB_D-, GND and +5V signals of USB host to USB device.`

			`#### Pin Assignment`

			`See common pin assignments for USB Device examples from [upper level](../../../README.md#common-pin-assignments).`

			`### Build and Flash`

usb: Extend CDC device with second CDC channel Closes https://github.com/espressif/esp-idf/issues/7020 Closes https://github.com/espressif/esp-idf/pull/8011 2021-12-16 01:50:08 -05:00			`1. Build and flash [tusb_serial_device example](../../../device/tusb_serial_device) to USB device board.`
usb: Add USB host CDC-ACM class driver 2021-07-16 04:01:15 -04:00			`2. Build this project and flash it to the USB host board, then run monitor tool to view serial output:`

			```bash
			`idf.py -p PORT flash monitor`
			```

			`(Replace PORT with the name of the serial port to use.)`

			(To exit the serial monitor, type ``Ctrl-]``.)

			`See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.`

usb_host: Use USB_Host library calls for desc printing 2022-02-11 14:26:35 -05:00			`### Running with dual USB CDC device`
			`USB CDC device example [tusb_serial_device example](../../../device/tusb_serial_device)`
			`can be configured to act as dual CDC device.`

			In the device example project, enter command `idf.py menuconfig` and set Component config->TinyUSB Stack->Communication Device Class (CDC)->CDC channel Count to `2`.

			This settings also changes device's PID, so `EXAMPLE_USB_DEVICE_PID` in [usb-cdc.c](./main/usb-cdc.c) must be changed to `0x4002`.


usb: Add USB host CDC-ACM class driver 2021-07-16 04:01:15 -04:00			`## Example Output`

			`After the flashing you should see the output at idf monitor:`

			```
usb_host: Use USB_Host library calls for desc printing 2022-02-11 14:26:35 -05:00			`...`
usb: Add USB host CDC-ACM class driver 2021-07-16 04:01:15 -04:00			`I (256) USB-CDC: USB Host installed`
			`I (256) USB-CDC: Opening CDC ACM device 0x303A:0x4001`
usb_host: Use USB_Host library calls for desc printing 2022-02-11 14:26:35 -05:00			`...`
			`Device descriptor is printed here`
			`...`
usb: Add USB host CDC-ACM class driver 2021-07-16 04:01:15 -04:00			`I (1666) USB-CDC: Data received`
			`I (1666) USB-CDC: 0x3ffc4c20 41 54 0d \|AT.\|`
			`I (2666) USB-CDC: Data received`
			`I (2666) USB-CDC: 0x3ffc4c20 41 54 2b 47 53 4e 0d \|AT+GSN.\|`
			`I (3666) USB-CDC: Setting up line coding`
			`I (3666) USB-CDC: Line Get: Rate: 115200, Stop bits: 0, Parity: 0, Databits: 8`
			`I (3666) USB-CDC: Line Set: Rate: 9600, Stop bits: 1, Parity: 1, Databits: 7`
			`I (3666) USB-CDC: Line Get: Rate: 9600, Stop bits: 1, Parity: 1, Databits: 7`
			`I (3676) Example finished successfully!`
			`...`

			```