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在 OLED SSD1306 上顯示二維條碼

tags: iota

SSD1306 模組為 128 x 64 Dot Matrix，與文字比較，使用二維條碼可儲存更多資料量，並讓使用者更容易取得資訊，如：Hash。選擇較通用、資料容量較大、可容錯的 QR code。

OLED SSD1306

  • 64 x 128
    • 16 x 128 黃色區塊
    • 48 x 128 藍色區塊
    • Image Not Showing Possible Reasons
      • The image file may be corrupted
      • The server hosting the image is unavailable
      • The image path is incorrect
      • The image format is not supported
      Learn More →
  • 實際可用為 48 x 128，橫跨兩區塊的 QR code 無法讀取
    • Image Not Showing Possible Reasons
      • The image file may be corrupted
      • The server hosting the image is unavailable
      • The image path is incorrect
      • The image format is not supported
      Learn More →

QR code 版本

  • 位元上限
    • 48 x 48
  • 資料量(英文數字混合)
    • TX hash: 81
    • Tag: 27
    • Address: 90
    • Message: 2187
  • 容錯能力
    • 一般情況下使用者大多選擇 M (15%)。
    • Level Tolerance
      L 7 %
      M 15 %
      Q 25 %
      H 30 %
  • 版本
  • 建議
    • 邊緣留白 4 bits
      • Image Not Showing Possible Reasons
        • The image file may be corrupted
        • The server hosting the image is unavailable
        • The image path is incorrect
        • The image format is not supported
        Learn More →
    • 每 bit 印 4 dots

QR code library

  • 使用 ricmoo/qrcode lib

    • QR code generation library in C, optimized for low-power devices, such as Arduino.

  • 結果

    • Image Not Showing Possible Reasons
      • The image file may be corrupted
      • The server hosting the image is unavailable
      • The image path is incorrect
      • The image format is not supported
      Learn More →
    • Image Not Showing Possible Reasons
      • The image file may be corrupted
      • The server hosting the image is unavailable
      • The image path is incorrect
      • The image format is not supported
      Learn More →

  • 測試

    • 容錯等級設為 Ｍ

    | 版本 | Size | 可顯示 | 可讀 | 容量(英文字母＋數字) |
    | –––– |–––– | –––– | –––– | –––– | –––– |
    | 1 | 21 x 21 | V | V | 20 |
    | 2 | 25 x 25 | V | V | 38 |
    | 3 | 29 x 29 | V | V | 61 |
    | 4 | 33 x 33 | V | V | 90 |
    | 5 | 37 x 37 | V | V | 122 |
    | 6 | 41 x 41 | V | V | 154 |
    | 7 | 45 x 45 | V | V | 178 |
    | 8 | 49 x 49 | X | X | 221 |

Reference

Last changed by 
 
ZAN-JUN WANG
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