是否可以在 UHF RFID 标签中读写 ASCII 字符？

Question

我正在为摩托罗拉 MC9190 RFID 手持阅读器开发一个应用程序。

我需要在 UHF RFID 标签中读取和写入人类可读的信息。所以我决定用 ASCII 字符来写信息。

在做一些研究时，我发现可以在 RFID 标签内存中写入 ASCII 字符，但它支持的字符较少。在少于 10 个字符之前我不会介意。

参考：

https://support.tracerplus.com/index.php?/Knowledgebase/Article/View/199/15/encoding-rfid-tags-with-ascii-values-vs-hexadecimal-values-whats-the-difference

http://blog.atlasrfidstore.com/types-of-memory-in-gen-2-uhf-rfid-tags

现在，我有点困惑如何直接在阅读器中读写 ASCII 字符。

这是用十六进制字符编写的代码。

private void writeButton_Click(object sender, EventArgs e)
{
    string dataToWrite="ABCDEF9876";
    Symbol.RFID3.TagAccess.WriteAccessParams m_WriteParams;

    m_WriteParams.AccessPassword = 0;

    m_WriteParams.MemoryBank = MEMORY_BANK.MEMORY_BANK_USER;
    m_WriteParams.ByteOffset = 0;
    m_WriteParams.WriteDataLength = 6;

    byte[] writeData = new byte[m_WriteParams.WriteDataLength];
    for (int index = 0; index < m_WriteParams.WriteDataLength; index += 2)
    {
        writeData[index] = byte.Parse(dataToWrite.Substring(index * 2, 2),
            System.Globalization.NumberStyles.HexNumber);
        writeData[index + 1] = byte.Parse(dataToWrite.Substring((index + 1) * 2, 2),
            System.Globalization.NumberStyles.HexNumber);
    }

    m_WriteParams.WriteData = writeData;
    string m_SelectedTagID = "0123456789ABCDEF";        //for example
    RunWriteOperation(m_SelectedTagID,m_WriteParams);
}


 void RunWriteOperation(string m_SelectedTagID,Symbol.RFID3.TagAccess.WriteAccessParams m_WriteParams)
 {
    if (m_SelectedTagID != String.Empty)
    {
        m_ReaderAPI.Actions.TagAccess.WriteWait(m_SelectedTagID,m_WriteParams, null);
    }
 }

如果我想用 ASCII 写，我猜它应该被编码为 ASCII 字节。所以不是for循环，如果我替换下面的代码，会不会写成功？

string dataToWrite="HELLOWORLD";
byte[] writeData = ASCIIEncoding.ASCII.GetBytes(dataToWrite);

由于我没有随身携带阅读器，所以我现在无法测试。

如果读取成功，在读取标签时，如何配置阅读器以解码为 ASCII 字符并显示它还是需要编程转换？

由于我是 RFID 技术的新手，我不确定我是否正确地完成了研究。如果我错了，请纠正我。

Answer 1

void hex2dec(unsigned adchex,unsigned value) 
{
unsigned value[4]; 

for(i=0;i<4;i++)
{
value[i]=adchex%10;
// value[i]=adchex%10+0x30; //for ASCII presentation
adchex=adchex/10; 
}
}

您还可以在此处查看此 SDK： http://www.tsl.uk.com/2013/07/tsls-ios-uhf-ascii-2-0-sdk-v0-8-1-now-available/

TSLAsciiCommands.framework - 一组易于使用的 Objective C 类，封装了 TSL UHF ASCII 2.0 协议，作为通用静态框架提供，可用于 iOS 设备和 iOS 模拟器 - TSL ASCII 2.0 SDK 文档 – 可作为文档集用于 Xcode 和 HTML 格式的集成 - 快速启动示例 Xcode 项目

---

如果您使用 TSLAsciiCommands 框架，您可以执行类似的操作。

-(void)initAndShowConnectedReader
{
if( _commander.isConnected )
{
    // Display the serial number of the successfully connected unit
    [self.selectReaderButton setTitle:_currentAccessory.serialNumber  forState:UIControlStateNormal];

    // Ensure the reader is in a known (default) state
    // No information is returned by the reset command
    TSLFactoryDefaultsCommand * resetCommand =  [TSLFactoryDefaultsCommand synchronousCommand];
    [_commander executeCommand:resetCommand];

    // Notify user device has been reset
    if( resetCommand.isSuccessful )
    {
        self.resultsTextView.text = [self.resultsTextView.text  stringByAppendingString:@"Reader reset to Factory Defaults\n"];
    }
    else
    {
        self.resultsTextView.text = [self.resultsTextView.text stringByAppendingString:@"!!! Unable to reset reader to Factory Defaults !!!\n"];
    }

    // Update the version information for the connected reader
    [_commander executeCommand:self.versionInformationCommand];

    if( [self.class comparableVersionValue:self.versionInformationCommand.asciiProtocol] < [self.class comparableVersionValue:MINIMUM_ASCII_PROTOCOL_VERSION_FOR_LICENCE_KEY_COMMAND] )
    {
        [self updateResults:[NSString stringWithFormat:@"Reader does not support licence keys\nRequires ASCII protocol: %@\nReader ASCII protocol: %@\n",
                             MINIMUM_ASCII_PROTOCOL_VERSION_FOR_LICENCE_KEY_COMMAND,
                             self.versionInformationCommand.asciiProtocol
                             ]];
    }
    [self validateReader];
}
else
{
    [self.selectReaderButton setTitle:@"Tap to select reader..." forState:UIControlStateNormal];
    [self updateUIState];
}
}

或

// Write data to general tag memory
string tagDataStr = "HELLO WORLD!";
byte[] tagData = ASCIIEncoding.ASCII.GetBytes(tagDataStr);
byte memBank = 0; // Different memory banks serve different purposes.      See MC9190 specifications.
int addr = 0;
byte words = (byte)(tagData.Length / 2); // Words = length of msg / 2

if (UHFWriteTagData(theHandle, readerType, memBank,addr, tagData,     (byte)tagData.Length, out errValue) == 0)
{
// Handle Error
}

// Read data from tag memory
byte[] readTagData = new byte[512];
int bytesRead;

if (UHFReadTagData(theHandle, readerType, memBank, addr, words,     readTagData,
readTagData.Length, out bytesRead, out errValue) == 0)
{
// Handle Error
}


// Display Results
string results =
"Input tag ID: " +
tagIDStr +
Environment.NewLine +
"Read tag ID: " +
ASCIIEncoding.ASCII.GetString(readTagID).Replace('\0','-') +
Environment.NewLine +
"Input tag data: " +
tagDataStr +
Environment.NewLine +
"Read tag data: " +
ASCIIEncoding.ASCII.GetString(readTagData).Replace('\0', '-').Substring(0,bytesRead) +
Environment.NewLine;

MessageBox.Show(results);