[fix gpio]

docs/soft/maixpy3/zh/usage/hardware/GPIO.ipynb

@@ -121,9 +121,9 @@
    "source": [
     "import time\n",
     "class BUTTON:\n",
-    "    def __init__(self, line, bank, chip, mode):\n",
+    "    def __init__(self, line, bank, chip=1, mode=2):\n",
     "        from maix import gpio\n",
-    "        self.button = gpio.gpio.gpio(line, bank, chip, mode)\n",
+    "        self.button = gpio.gpio(line, bank, chip, mode)\n",
     "    def is_pressed(self):\n",
     "        if self.button.get_value() != 1:\n",
     "            return True\n",
@@ -131,7 +131,7 @@
     "        self.button.release()\n",
     "\n",
     "global key\n",
-    "key = BUTTON(6, 2)\n",
+    "key = BUTTON(6, \"H\")\n",
     "print(key.button.source)"
    ]
   },

docs/soft/maixpy3/zh/usage/vision/maixpy3-example.ipynb

@@ -671,7 +671,9 @@
    "source": [
     "## 【传统视觉基础】寻线寻迹\n",
     "\n",
-    "找线算法是面对小车寻线而开发的一个算法。主要的流程是，灰度化 -> 自适应阈值处理 -> 形态学运算 -> 图像最小二乘法。完成算法流程后返回一条线的信息，让小车能够根据识别出来线的信息进行运动。这个接口比较适合做图像寻线。\n"
+    "找线算法是面对小车寻线而开发的一个算法。主要的流程是，灰度化 -> 自适应阈值处理 -> 形态学运算 -> 图像最小二乘法。完成算法流程后返回一条线的信息，让小车能够根据识别出来线的信息进行运动。这个接口比较适合做图像寻线。\n",
+    "\n",
+    "对应实现 https://github.com/sipeed/MaixPy3/blob/release/ext_modules/_maix_image/_maix_vision.cpp#L513-L612\n"
    ]
   },
   {