arduino 查表实现gbk转uf-8

将GBK编码转换成UTF-8编码可以通过查表实现。下面是一个基于Arduino的查表实现示例代码：

#include <Arduino.h>

// GBK到UTF-8编码的映射表
const uint16_t gbk2utf8[][2] = {
  {0x8140, 0xE38080}, {0x8141, 0xE38081}, {0x8142, 0xE38082}, {0x8143, 0xE38083}, {0x8144, 0xE38084},
  // 其他映射关系...
};

// 将GBK编码转换成UTF-8编码
void gbk2utf8(const uint8_t *gbk, uint8_t *utf8) {
  uint16_t gbkCode = (gbk[0] << 8) | gbk[1];
  uint32_t utf8Code = 0;

  // 查表映射
  for (size_t i = 0; i < sizeof(gbk2utf8) / sizeof(gbk2utf8[0]); i++) {
    if (gbkCode == gbk2utf8[i][0]) {
      utf8Code = gbk2utf8[i][1];
      break;
    }
  }

  // 将UTF-8编码写入输出缓存
  if (utf8Code != 0) {
    if (utf8Code <= 0x7F) {
      utf8[0] = (uint8_t)utf8Code;
    } else if (utf8Code <= 0x7FF) {
      utf8[0] = (uint8_t)(0xC0 | ((utf8Code >> 6) & 0x1F));
      utf8[1] = (uint8_t)(0x80 | (utf8Code & 0x3F));
    } else if (utf8Code <= 0xFFFF) {
      utf8[0] = (uint8_t)(0xE0 | ((utf8Code >> 12) & 0x0F));
      utf8[1] = (uint8_t)(0x80 | ((utf8Code >> 6) & 0x3F));
      utf8[2] = (uint8_t)(0x80 | (utf8Code & 0x3F));
    } else if (utf8Code <= 0x10FFFF) {
      utf8[0] = (uint8_t)(0xF0 | ((utf8Code >> 18) & 0x07));
      utf8[1] = (uint8_t)(0x80 | ((utf8Code >> 12) & 0x3F));
      utf8[2] = (uint8_t)(0x80 | ((utf8Code >> 6) & 0x3F));
      utf8[3] = (uint8_t)(0x80 | (utf8Code & 0x3F));
    }
  }
}

void setup() {
  Serial.begin(9600);

  uint8_t gbk[] = {0xB2, 0xE2};
  uint8_t utf8[4] = {0};

  gbk2utf8(gbk, utf8);

  Serial.print("GBK: ");
  for (size_t i = 0; i < sizeof(gbk); i++) {
    Serial.print(gbk[i], HEX);
    Serial.print(" ");
  }
  Serial.println();

  Serial.print("UTF-8: ");
  for (size_t i = 0; i < sizeof(utf8); i++) {
    Serial.print(utf8[i], HEX);
    Serial.print(" ");
  }
  Serial.println();
}

void loop() {
}

在这个示例中，我们定义了一个`gbk2utf8`函数，该函数接受一个指向GBK编码的指针和一个指向输出UTF-8编码的指针。函数将GBK编码转换为UTF-8编码，并将结果存储在输出缓存中。实际的转换是通过查找映射表来完成的。在映射表中，我们将每个GBK编码映射到一个对应的UTF-8编码。一旦找到匹配项，我们就可以将UTF-8编码写入输出缓存中。

在`setup`函数中，我们定义了一个GBK编码，并将其转换为UTF-8编码。我们然后使用`Serial.print`函数将转换前后的编码打印到串口监视器中。