gabrieledcjr · March 9, 2019 05:34 · Feb 7, 2014
diff --git a/js_linux.py b/js_linux.py
@@ -0,0 +1,159 @@
+# Released by rdb under the Unlicense (unlicense.org)
+# Based on information from:
+# https://www.kernel.org/doc/Documentation/input/joystick-api.txt
+
+import os, struct, array
+from fcntl import ioctl
+
+# Iterate over the joystick devices.
+print('Available devices:')
+
+for fn in os.listdir('/dev/input'):
+    if fn.startswith('js'):
+        print('  /dev/input/%s' % (fn))
+
+# We'll store the states here.
+axis_states = {}
+button_states = {}
+
+# These constants were borrowed from linux/input.h
+axis_names = {
+    0x00 : 'x',
+    0x01 : 'y',
+    0x02 : 'z',
+    0x03 : 'rx',
+    0x04 : 'ry',
+    0x05 : 'rz',
+    0x06 : 'trottle',
+    0x07 : 'rudder',
+    0x08 : 'wheel',
+    0x09 : 'gas',
+    0x0a : 'brake',
+    0x10 : 'hat0x',
+    0x11 : 'hat0y',
+    0x12 : 'hat1x',
+    0x13 : 'hat1y',
+    0x14 : 'hat2x',
+    0x15 : 'hat2y',
+    0x16 : 'hat3x',
+    0x17 : 'hat3y',
+    0x18 : 'pressure',
+    0x19 : 'distance',
+    0x1a : 'tilt_x',
+    0x1b : 'tilt_y',
+    0x1c : 'tool_width',
+    0x20 : 'volume',
+    0x28 : 'misc',
+}
+
+button_names = {
+    0x120 : 'trigger',
+    0x121 : 'thumb',
+    0x122 : 'thumb2',
+    0x123 : 'top',
+    0x124 : 'top2',
+    0x125 : 'pinkie',
+    0x126 : 'base',
+    0x127 : 'base2',
+    0x128 : 'base3',
+    0x129 : 'base4',
+    0x12a : 'base5',
+    0x12b : 'base6',
+    0x12f : 'dead',
+    0x130 : 'a',
+    0x131 : 'b',
+    0x132 : 'c',
+    0x133 : 'x',
+    0x134 : 'y',
+    0x135 : 'z',
+    0x136 : 'tl',
+    0x137 : 'tr',
+    0x138 : 'tl2',
+    0x139 : 'tr2',
+    0x13a : 'select',
+    0x13b : 'start',
+    0x13c : 'mode',
+    0x13d : 'thumbl',
+    0x13e : 'thumbr',
+
+    0x220 : 'dpad_up',
+    0x221 : 'dpad_down',
+    0x222 : 'dpad_left',
+    0x223 : 'dpad_right',
+
+    # XBox 360 controller uses these codes.
+    0x2c0 : 'dpad_left',
+    0x2c1 : 'dpad_right',
+    0x2c2 : 'dpad_up',
+    0x2c3 : 'dpad_down',
+}
+
+axis_map = []
+button_map = []
+
+# Open the joystick device.
+fn = '/dev/input/js0'
+print('Opening %s...' % fn)
+jsdev = open(fn, 'rb')
+
+# Get the device name.
+#buf = bytearray(63)
+buf = array.array('c', ['\0'] * 64)
+ioctl(jsdev, 0x80006a13 + (0x10000 * len(buf)), buf) # JSIOCGNAME(len)
+js_name = buf.tostring()
+print('Device name: %s' % js_name)
+
+# Get number of axes and buttons.
+buf = array.array('B', [0])
+ioctl(jsdev, 0x80016a11, buf) # JSIOCGAXES
+num_axes = buf[0]
+
+buf = array.array('B', [0])
+ioctl(jsdev, 0x80016a12, buf) # JSIOCGBUTTONS
+num_buttons = buf[0]
+
+# Get the axis map.
+buf = array.array('B', [0] * 0x40)
+ioctl(jsdev, 0x80406a32, buf) # JSIOCGAXMAP
+
+for axis in buf[:num_axes]:
+    axis_name = axis_names.get(axis, 'unknown(0x%02x)' % axis)
+    axis_map.append(axis_name)
+    axis_states[axis_name] = 0.0
+
+# Get the button map.
+buf = array.array('H', [0] * 200)
+ioctl(jsdev, 0x80406a34, buf) # JSIOCGBTNMAP
+
+for btn in buf[:num_buttons]:
+    btn_name = button_names.get(btn, 'unknown(0x%03x)' % btn)
+    button_map.append(btn_name)
+    button_states[btn_name] = 0
+
+print '%d axes found: %s' % (num_axes, ', '.join(axis_map))
+print '%d buttons found: %s' % (num_buttons, ', '.join(button_map))
+
+# Main event loop
+while True:
+    evbuf = jsdev.read(8)
+    if evbuf:
+        time, value, type, number = struct.unpack('IhBB', evbuf)
+
+        if type & 0x80:
+             print "(initial)",
+
+        if type & 0x01:
+            button = button_map[number]
+            if button:
+                button_states[button] = value
+                if value:
+                    print "%s pressed" % (button)
+                else:
+                    print "%s released" % (button)
+
+        if type & 0x02:
+            axis = axis_map[number]
+            if axis:
+                fvalue = value / 32767.0
+                axis_states[axis] = fvalue
+                print "%s: %.3f" % (axis, fvalue)