code: public static byte[] strToBcd(String asc) {
  		int len = asc.length();
  		int mod = len % 2;
  		if (mod != 0) {
  			asc = "0" + asc;
  			len = asc.length();
  		}
  		byte abt[] = new byte[len];
  		if (len >= 2) {
  			len >>= 1;
  		}
  		byte bbt[] = new byte[len];
  		abt = asc.getBytes();
  		int j;
  		int k;
  		for (int p = 0; p < asc.length() / 2; p++) {
  			if ((abt[2 * p] >= '0') && (abt[2 * p] <= '9')) {
  				j = abt[2 * p] - '0';
  			} else if ((abt[2 * p] >= 'a') && (abt[2 * p] <= 'z')) {
  				j = abt[2 * p] - 'a' + 0x0a;
  			} else {
  				j = abt[2 * p] - 'A' + 0x0a;
  			}
  			if ((abt[2 * p + 1] >= '0') && (abt[2 * p + 1] <= '9')) {
  				k = abt[2 * p + 1] - '0';
  			} else if ((abt[2 * p + 1] >= 'a') && (abt[2 * p + 1] <= 'z')) {
  				k = abt[2 * p + 1] - 'a' + 0x0a;
  			} else {
  				k = abt[2 * p + 1] - 'A' + 0x0a;
  			}
  			int a = (j << 4) + k;
  			byte b = (byte) a;
  			bbt[p] = b;
  		}
  		return bbt;
  	}
docs: 字符串转BCD码
  @param asc ASCII字符串
  @return BCD