basic mouse circuitpython example

Author: FoamyGuy

USB_Host_Examples/CircuitPython_Mouse_Basic/code.py

@@ -0,0 +1,70 @@
+# SPDX-FileCopyrightText: 2025 Tim Cocks for Adafruit Industries
+# SPDX-License-Identifier: MIT
+"""
+This example is made for a basic mouse with
+two buttons and a wheel that can be pressed.
+
+It assumes there is a single mouse connected to USB Host.
+"""
+import array
+import usb.core
+import adafruit_usb_host_descriptors
+
+# button names
+# This is ordered by bit position.
+BUTTONS = ["left", "right", "middle"]
+
+# scan for connected USB device and loop over any found
+for device in usb.core.find(find_all=True):
+    # print device info
+    print(f"{device.idVendor:04x}:{device.idProduct:04x}")
+    print(device.manufacturer, device.product)
+    print(device.serial_number)
+
+    # try to find mouse endpoint on the current device.
+    mouse_interface_index, mouse_endpoint_address = (
+        adafruit_usb_host_descriptors.find_boot_mouse_endpoint(device)
+    )
+    if mouse_interface_index is not None and mouse_endpoint_address is not None:
+        mouse = device
+        print(
+            f"mouse interface: {mouse_interface_index} "
+            + f"endpoint_address: {hex(mouse_endpoint_address)}"
+        )
+
+        # detach the kernel driver if needed
+        if mouse.is_kernel_driver_active(0):
+            mouse.detach_kernel_driver(0)
+
+        # set configuration on the mouse so we can use it
+        mouse.set_configuration()
+
+        break
+
+# buffer to hold mouse data
+buf = array.array("b", [0] * 8)
+
+# main loop
+while True:
+    try:
+        # attempt to read data from the mouse
+        # 10ms timeout, so we don't block long if there
+        # is no data
+        count = mouse.read(0x81, buf, timeout=10)
+    except usb.core.USBTimeoutError:
+        # skip the rest of the loop if there is no data
+        continue
+
+    # string with delta x, y values to print
+    out_str = f"{buf[1]},{buf[2]}"
+
+    # loop over the button names
+    for i, button in enumerate(BUTTONS):
+        # check if each button is pressed using bitwise AND shifted
+        # to the appropriate index for this button
+        if buf[0] & (1 << i) != 0:
+            # append the button name to the string to show if
+            # it is being clicked.
+            out_str += f" {button}"
+
+    print(out_str)