http://fileformats.archiveteam.org/index.php?action=history&feed=atom&title=FM_encoding 2026-04-19T03:59:06Z Revision history for this page on the wiki MediaWiki 1.19.2 http://fileformats.archiveteam.org/index.php?title=FM_encoding&diff=33257&oldid=prev 2019-09-04T23:41:51Z

<p>‎<span dir="auto"><span class="autocomment">Floppy disk formats using FM encoding</span></span></p> <table class='diff diff-contentalign-left'> <col class='diff-marker' /> <col class='diff-content' /> <col class='diff-marker' /> <col class='diff-content' /> <tr valign='top'> <td colspan='2' style="background-color: white; color:black;">← Older revision</td> <td colspan='2' style="background-color: white; color:black;">Revision as of 23:41, 4 September 2019</td> </tr><tr><td colspan="2" class="diff-lineno">Line 15:</td> <td colspan="2" class="diff-lineno">Line 15:</td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM Type 2]] (43FD)</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM Type 2]] (43FD)</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 23FD]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 23FD]]</div></td></tr> <tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>* [[IBM 3740]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>* [[IBM 3740 <ins class="diffchange diffchange-inline">format</ins>]]</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>== Links ==</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>== Links ==</div></td></tr> </table>

Dan Tobias http://fileformats.archiveteam.org/index.php?title=FM_encoding&diff=11461&oldid=prev 2013-05-08T20:50:47Z

<p></p> <table class='diff diff-contentalign-left'> <col class='diff-marker' /> <col class='diff-content' /> <col class='diff-marker' /> <col class='diff-content' /> <tr valign='top'> <td colspan='2' style="background-color: white; color:black;">← Older revision</td> <td colspan='2' style="background-color: white; color:black;">Revision as of 20:50, 8 May 2013</td> </tr><tr><td colspan="2" class="diff-lineno">Line 19:</td> <td colspan="2" class="diff-lineno">Line 19:</td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>== Links ==</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>== Links ==</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[Wikipedia:Differential Manchester encoding|Wikipedia article]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[Wikipedia:Differential Manchester encoding|Wikipedia article]]</div></td></tr> <tr><td colspan="2">&#160;</td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;"></ins></div></td></tr> <tr><td colspan="2">&#160;</td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;">[[Category:Magnetic tape]]</ins></div></td></tr> </table>

Dan Tobias http://fileformats.archiveteam.org/index.php?title=FM_encoding&diff=11395&oldid=prev 2013-05-05T04:15:09Z

<p>‎<span dir="auto"><span class="autocomment">Floppy disk formats using FM encoding</span></span></p> <table class='diff diff-contentalign-left'> <col class='diff-marker' /> <col class='diff-content' /> <col class='diff-marker' /> <col class='diff-content' /> <tr valign='top'> <td colspan='2' style="background-color: white; color:black;">← Older revision</td> <td colspan='2' style="background-color: white; color:black;">Revision as of 04:15, 5 May 2013</td> </tr><tr><td colspan="2" class="diff-lineno">Line 12:</td> <td colspan="2" class="diff-lineno">Line 12:</td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[Atari 810]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[Atari 810]]</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[DEC RX01]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[DEC RX01]]</div></td></tr> <tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del class="diffchange diffchange-inline">*</del>* [[IBM Type 1]] (33FD)</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>* [[IBM Type 1]] (33FD)</div></td></tr> <tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del class="diffchange diffchange-inline">*</del>* [[IBM Type 2]] (43FD)</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>* [[IBM Type 2]] (43FD)</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 23FD]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 23FD]]</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 3740]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 3740]]</div></td></tr> </table>

Dan Tobias http://fileformats.archiveteam.org/index.php?title=FM_encoding&diff=11394&oldid=prev 2013-05-05T04:14:57Z

<p>‎<span dir="auto"><span class="autocomment">Floppy disk formats using FM encoding</span></span></p> <table class='diff diff-contentalign-left'> <col class='diff-marker' /> <col class='diff-content' /> <col class='diff-marker' /> <col class='diff-content' /> <tr valign='top'> <td colspan='2' style="background-color: white; color:black;">← Older revision</td> <td colspan='2' style="background-color: white; color:black;">Revision as of 04:14, 5 May 2013</td> </tr><tr><td colspan="2" class="diff-lineno">Line 12:</td> <td colspan="2" class="diff-lineno">Line 12:</td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[Atari 810]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[Atari 810]]</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[DEC RX01]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[DEC RX01]]</div></td></tr> <tr><td colspan="2">&#160;</td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;">** [[IBM Type 1]] (33FD)</ins></div></td></tr> <tr><td colspan="2">&#160;</td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;">** [[IBM Type 2]] (43FD)</ins></div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 23FD]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 23FD]]</div></td></tr> <tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del style="color: red; font-weight: bold; text-decoration: none;">* [[IBM 33FD]]</del></div></td><td colspan="2">&#160;</td></tr> <tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del style="color: red; font-weight: bold; text-decoration: none;">* [[IBM 43FD]]</del></div></td><td colspan="2">&#160;</td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 3740]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[IBM 3740]]</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>== Links ==</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>== Links ==</div></td></tr> <tr><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[Wikipedia:Differential Manchester encoding|Wikipedia article]]</div></td><td class='diff-marker'>&#160;</td><td style="background: #eee; color:black; font-size: smaller;"><div>* [[Wikipedia:Differential Manchester encoding|Wikipedia article]]</div></td></tr> </table>

Dan Tobias http://fileformats.archiveteam.org/index.php?title=FM_encoding&diff=11389&oldid=prev 2013-05-04T23:59:03Z

<p>Created page with &quot;{{FormatInfo |formattype=physical |subcat=Floppy disk }} &#039;&#039;&#039;FM encoding&#039;&#039;&#039; (which stands for Frequency Modulation, just as it does with <a href="/wiki/FM" title="FM">FM</a> radio) is a method of encoding ...&quot;</p> <p><b>New page</b></p><div>{{FormatInfo<br /> |formattype=physical<br /> |subcat=Floppy disk<br /> }}<br /> <br /> '''FM encoding''' (which stands for Frequency Modulation, just as it does with [[FM]] radio) is a method of encoding data bits for storage or transmission, also known as '''Differential Manchester encoding''' or '''biphase mark code''' (BMC). It is used in some formats of [[floppy disk]] and [[magnetic tape]], as well as in networking protocols.<br /> <br /> The essential characteristic is that bits are encoded by the change in signal from one part of the medium to another, rather than the absolute value of the signal at any point. A &quot;1&quot; bit might be encoded as a change from &quot;on&quot; to &quot;off&quot;, or from &quot;off&quot; to &quot;on&quot;, depending on where the signal was left at the end of the previous bit. A &quot;0&quot; bit would be encoded by a different set of signal changes, perhaps two in rapid succession leaving the signal at the same state it started at. This characteristic allows the content to remain unchanged when the signal is completely inverted.<br /> <br /> == Floppy disk formats using FM encoding ==<br /> * [[Acorn single density 5 1/4&quot; disk]]<br /> * [[Atari 810]]<br /> * [[DEC RX01]]<br /> * [[IBM 23FD]]<br /> * [[IBM 33FD]]<br /> * [[IBM 43FD]]<br /> * [[IBM 3740]]<br /> <br /> == Links ==<br /> * [[Wikipedia:Differential Manchester encoding|Wikipedia article]]</div>

Dan Tobias