usage/tips/xmodem.html

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<h1>Tips on XMODEM</h1>

<h2>8bit clean</h2>

<p>
The XMODEM file transfer protocol requires the communication lines to be transparent to all 8 bit characters, from $00 to $FF.
</p>

<h3>For serial port:</h3>

<div class="indent1">
<p>
Set the appropriate parameters in the <A HREF="../../menu/setup-serialport.html">[Setup] Serial port</A> dialog box. Data must be 8 bit, and Flow control must be hard (CTS/RTS) or none.
</p>
</div>

<h3>For telnet:</h3>

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<p>
If file transfers fail, try connecting to the host with the binary option. To connect with the binary option:
</p>

<ul class="no-marker">
  <li class="description">Specify the /B option on the <A HREF="../../commandline/teraterm.html">command line</A>, or</li>
  <li class="description">Edit the setup file.<br>
<a href="../../setup/teraterm-com.html#telbin">Telnet binary option</a></li>
</ul>
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<h2 id="padding">padding at end of file</h2>

<p>
The XMODEM file transfer protocol handles files in blocks of 128 or
1024 bytes, and file lengths cannot be exchanged.

The received data length is always a multiple of 128 or 1024 bytes.
</p>

<p>
Sender puts padding in the last block that is longer than the length
of the transmitted file.

The padding is $1A according to the XMODEM specification.
But it may be some other value depending on the XMODEM sending program.
</p>

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