{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "オリジナルの作成: 2014/12/13" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# 07-LEDで文字を表示する\n", "今回はクリスマスも近くなので、参加者の皆さんと話し合ってLEDで文字を表示してみようと いうことになりました。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 文字を表示するブレッドボード\n", "文字を表示するために、７個のLEDを使います。\n", "\n", "以下の様に、Arduino Mini Pro, LED, 抵抗1\n", "を配線します。\n", "\n", "LEDとArduinoとの間は、手元にある線の長さで自由につないで下さい。 図では、分かりやすいように順番でつないでいます。\n", "\n", "" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### LEDがきちんと点灯するか確かめる\n", "一番右（振るときには一番上）のLEDから0〜6番と番号を付けて、各LEDがつながっているデジタルピンの 番号をledsにセットします。\n", "\n", "以下のスケッチでLEDが順番に点灯し、最後にすべて点灯するか確かめて下さい。\n", "\n", "```C++\n", "#define NUM_OF_LED (7)\n", "#define NUM_OF_CHARS (8)\n", "\n", "static int mojiStr[][NUM_OF_LED] = {\n", " {1,0,0,0,0,0,0},\n", " {0,1,0,0,0,0,0},\n", " {0,0,1,0,0,0,0},\n", " {0,0,0,1,0,0,0},\n", " {0,0,0,0,1,0,0},\n", " {0,0,0,0,0,1,0},\n", " {0,0,0,0,0,0,1},\n", " {1,1,1,1,1,1,1}\n", " };\n", " \n", "static int leds[] = {3,4,5,6,9,8,7}; \n", "\n", "void setup() {\n", " for (int i = 0; i < NUM_OF_LED; i++) {\n", " pinMode(leds[i], OUTPUT);\n", " }\n", "}\n", "\n", "void loop() {\n", " for (int i = 0; i < NUM_OF_CHARS; i++) {\n", " for (int j = 0; j < NUM_OF_LED; j++) {\n", " digitalWrite(leds[j], mojiStr[i][j]);\n", " }\n", " delay(500);\n", " }\n", "}\n", "```" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### 配列の話し\n", "ledsやmojiStrは配列と呼ばれるものです。\n", "\n", "これまで、配列についてきちんと説明していなかったので、 ここで改めて配列って何なのか説明します。\n", "\n", "配列は、複数の値を連続した領域に保存したもので、［］の中に添え字と呼ばれる数値または変数を 使って配列の中の値を読み込んだり、セットしたりすることができます。\n", "\n", "ledsは、１個の［］で定義された１次元配列です。 ledsという変数は、数値3, 4, 5, 6, 9, 8, 7が連続して保存された領域を指し、添え字を使って値を取って きます。\n", "\n", "配列の添え字は、０からはじまっており、配列ledsから２番目の4の値を取ってくるときには、\n", "\n", "```C++\n", "leds[1]\n", "```\n", "\n", "のように書きます。\n", "\n", "先ほどのスケッチのsetup関数では、変数iを使ってledsに入っているデジタルピン番号を使って pinModeをOUTPUTにしています。\n", "\n", "```C++\n", " for (int i = 0; i < NUM_OF_LED; i++) {\n", " pinMode(leds[i], OUTPUT);\n", " }\n", "```\n", "\n", "\n", "\n", "次に２個の［］で定義された２次元配列mojiStrをみてみましょう。 mojiStrの値は、以下の様にセットされています。\n", "\n", "\n", "\n", "2次元配列は、1次元配列を縦にしたものと各行の値を持っている2つの領域に保存されています。\n", "\n", "mojiStr[0]と指定すると一番上の1,0,0,0,0,0,0が入った領域を指し、mojiStr[0][0]と1番上の行の最初の値1を取ってきます。\n", "\n", "このようにして、7個のLEDの値を添え字jのループでセットしているのが、loop関数の以下の部分です。\n", "\n", "```C++\n", " for (int j = 0; j < NUM_OF_LED; j++) {\n", " digitalWrite(leds[j], mojiStr[i][j]);\n", " }\n", "```\n", "\n", "少しずつ点灯しているLEDを変えることで、文字のが形を作り出すのが今回の目的です。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 左右対称の文字の表示 \n", "縦に並んだLEDを左右に振ることで、文字のような形を写しだしてみましょう。\n", "\n", "表示する文字（図形）は、左右対称であれば何でもかまいません。\n", "\n", "以下のスケッチでは、「TAO」を表示してみます。\n", "\n", "```C++\n", "#define NUM_OF_LED (7)\n", "#define NUM_OF_HEIGHT NUM_OF_LED\n", "#define NUM_OF_WIDTH (5)\n", "#define NUM_OF_CHARS (3)\n", "static int mojiStr[][NUM_OF_HEIGHT][NUM_OF_WIDTH] = {\n", " // TAO\n", " { {1,1,1,1,1},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0} },\n", "\n", " { {0,0,1,0,0},\n", " {0,1,0,1,0},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {1,1,1,1,1},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1} },\n", "\n", " { {0,1,1,1,0},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {0,1,1,1,0} }\n", "}; \n", " \n", "static int leds[] = {3,4,5,6,9,8,7}; \n", "\n", "void setup() {\n", " for (int i = 0; i < NUM_OF_LED; i++) {\n", " pinMode(leds[i], OUTPUT);\n", " }\n", "}\n", "\n", "void loop() {\n", " for (int i = 0; i < NUM_OF_CHARS; i++) {\n", " for (int j = 0; j < NUM_OF_WIDTH; j++) {\n", " for (int k = 0; k < NUM_OF_HEIGHT; k++) {\n", " digitalWrite(leds[k], mojiStr[i][k][j]);\n", " }\n", " delay(4);\n", " }\n", " delay(8);\n", " }\n", "}\n", "```" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### スケッチの説明 \n", "できるだけ、文字の形を確認しながら動かしたいので、mojiStrには3次元の配列にしました。\n", "\n", "3次元の配列は、2次元の配列が何枚も重なっているようなものをイメージすると分かりやすいと思います。\n", "\n", "loop関数のforループの一番内側では、i, j, kの添え字が、i, k, jとなっているところがポイントです。\n", "\n", "```C++\n", " digitalWrite(leds[k], mojiStr[i][k][j]);\n", "```\n", "\n", "このようにループの順番を変えることで、表示順と定義の順番を入れ替えています。\n", "\n", "LEDを左右に振ると何となくT, O, Aに似た文字が出てくると思います。" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## 振る方向で表示の順番を変える\n", "3軸の加速度をアナログ電圧で出力するセンサーKXM52-1050\n", "2\n", "を使ってY軸（横方向）の加速度から振る方向を判断して、文字を表示する順番を変えてみました。\n", "\n", "以下の様にKXM52-1050をつなぎます。\n", "\n", "\n", "\n", "ブレッドボードは、以下の様に作成しました。\n", "\n", "" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### スケッチ\n", "まだ、完成とまでは言えませんが、現段階のスケッチを以下に示します。\n", "\n", "```C++\n", "#define NUM_OF_LED (7)\n", "#define NUM_OF_HEIGHT NUM_OF_LED\n", "#define NUM_OF_WIDTH (5)\n", "#define NUM_OF_CHARS (3)\n", "#define ZERO 505\n", "#define SHIKI_CHI 200\n", "static int mojiStr[][NUM_OF_HEIGHT][NUM_OF_WIDTH] = {\n", " // TAO\n", " { {1,1,1,1,1},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0},\n", " {0,0,1,0,0} },\n", "\n", " { {0,0,1,0,0},\n", " {0,1,0,1,0},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {1,1,1,1,1},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1} },\n", "\n", " { {0,1,1,1,0},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {1,0,0,0,1},\n", " {0,1,1,1,0} }\n", "}; \n", " \n", "static int leds[] = {3,4,5,6,9,8,7}; \n", "int dir = 1;\n", "int start_i = 0;\n", "int start_j = 0;\n", "static int accPin = A1;\n", "\n", "void setup() {\n", " Serial.begin(9600);\n", " Serial.println(\"Output acc value\");\n", " for (int i = 0; i < NUM_OF_LED; i++) {\n", " pinMode(leds[i], OUTPUT);\n", " }\n", "}\n", "\n", "void loop() {\n", " int value = analogRead(accPin);\n", " // Serial.println(value);\n", " // delay(100);\n", " if (abs(value - ZERO) >= SHIKI_CHI) {\n", " // 方向に合わせて順序を変える\n", " if (value - ZERO > 0) {\n", " dir = -1;\n", " start_j = NUM_OF_WIDTH-1;\n", " start_i = NUM_OF_CHARS-1;\n", " }\n", " else {\n", " dir = 1;\n", " start_j = 0;\n", " start_i = 0;\n", " }\n", " int ii = 0;\n", " int jj = 0;\n", " for (int i = 0; i < NUM_OF_CHARS; i++) {\n", " ii = dir < 0 ? start_i - i : 0;\n", " for (int j = 0; j < NUM_OF_WIDTH; j++) {\n", " jj = dir < 0 ? start_j - j : 0;\n", " for (int k = 0; k < NUM_OF_HEIGHT; k++) {\n", " digitalWrite(leds[k], mojiStr[ii][k][jj]);\n", " }\n", " delay(4);\n", " }\n", " // 消灯\n", " for (int k = 0; k < NUM_OF_HEIGHT; k++) {\n", " digitalWrite(leds[k], 0);\n", " }\n", " delay(4);\n", " }\n", " // 消灯\n", " for (int k = 0; k < NUM_OF_HEIGHT; k++) {\n", " digitalWrite(leds[k], 0);\n", " }\n", " }\n", "}\n", "```\n", "\n", "文字は、はっきりしませんが、以下の様にでました。\n", "\n", "" ] }, { "cell_type": "markdown", "metadata": { "collapsed": true }, "source": [ "## 脚注\n", "\n", "- 1 手元にあった470Ωを使っています\n", "- 2 秋月のXSC7-2050等も使用可能、ただし軸のピンの配置が異なります" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [] } ], "metadata": { "kernelspec": { "display_name": "Python 2", "language": "python", "name": "python2" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 2 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython2", "version": "2.7.13" } }, "nbformat": 4, "nbformat_minor": 0 }