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<?xml-stylesheet type="text/xsl" href="https://community.arm.com/utility/feedstylesheets/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/"><channel><title>inforamtion about 8255 interfacing with 8051 microcontrollers</title><link>https://community.arm.com/developer/tools-software/tools/f/keil-forum/19587/inforamtion-about-8255-interfacing-with-8051-microcontrollers</link><description> how to interface 8255 IC with 8051 microcontroller. </description><dc:language>en-US</dc:language><generator>Telligent Community 10</generator><item><title>RE: inforamtion about 8255 interfacing with 8051 microcontrollers</title><link>https://community.arm.com/thread/111857?ContentTypeID=1</link><pubDate>Wed, 28 Dec 2005 19:55:29 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:01ed57d3-d8ce-405a-90c7-17938710646b</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;i&gt;&amp;quot;Are you making something from a book by an author that is too lazy to update to current technology?&amp;quot;&lt;/i&gt;&lt;br /&gt;
&lt;br /&gt;
it might not be the book Author&amp;#39;s fault - maybe the OP has just found an old book in the library, or a second-hand bookshop, or a skip, or something...&lt;br /&gt;
&lt;br /&gt;
&lt;i&gt;&amp;quot;or are you in school being taught by an instructor that is too lazy to update to current technology?&amp;quot;&lt;/i&gt;&lt;br /&gt;
&lt;br /&gt;
If this is purely a (school) exercise in interfacing something to an 8051 (or derivative), then it&amp;#39;s probably perfectly worthwhile &lt;i&gt;for the purpose of the exercise&lt;/i&gt;.&lt;br /&gt;
In this case, the school would presumably provide the necessary materials (datasheets, etc) as handouts, in textbooks, or whatever.&lt;br /&gt;
This would seem like a perfectly valid exercise in reading a datasheet &amp;amp; implementing its requirements - &lt;b&gt;just so long as the students understand that it is &lt;i&gt;not&lt;/i&gt; an illustration of current practice!&lt;/b&gt;&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: inforamtion about 8255 interfacing with 8051 microcontrollers</title><link>https://community.arm.com/thread/97750?ContentTypeID=1</link><pubDate>Wed, 28 Dec 2005 19:47:42 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:00f1e735-17a6-4dd8-96f7-0c04ed4c6342</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;i&gt;&amp;quot;Note that the 8255 is obsolete, and has been obsolete for many years.&amp;quot;&lt;/i&gt;&lt;br /&gt;
&lt;br /&gt;
&lt;i&gt;&amp;quot;You could in all fairness say the same thing about the 8051.&amp;quot;&lt;/i&gt;&lt;br /&gt;
&lt;br /&gt;
Yes, the actual Intel 8051 &lt;i&gt;chip&lt;/i&gt; itself is obsolete; but the 8051 &lt;i&gt;architecture&lt;/i&gt; is most certainly alive and well, with many current derivates, and new products being introduced all the time.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: inforamtion about 8255 interfacing with 8051 microcontrollers</title><link>https://community.arm.com/thread/87527?ContentTypeID=1</link><pubDate>Wed, 28 Dec 2005 19:35:40 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:b31a16c9-1729-4647-93d2-2d65bc8e00b5</guid><dc:creator>Drew Davis</dc:creator><description>&lt;p&gt;&lt;i&gt;Note that the 8255 is obsolete, and has been obsolete for many years.&lt;/i&gt;&lt;br /&gt;
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You could in all fairness say the same thing about the 8051.  But then, you don&amp;#39;t always need the latest technology to solve a problem.&lt;br /&gt;
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I agree that a newer 8051 derivative with extended interrupt support would seem to be a better solution to the problem, though.  A board with fewer chips is generally cheaper, lower power, more reliable, and easier to debug.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: inforamtion about 8255 interfacing with 8051 microcontrollers</title><link>https://community.arm.com/thread/97748?ContentTypeID=1</link><pubDate>Tue, 27 Dec 2005 08:59:25 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:15d3c25a-2b61-410a-af16-5fbc0fcaffc1</guid><dc:creator>erik  malund</dc:creator><description>&lt;p&gt;&lt;i&gt;Here you may meet your first problem: where will you find the datasheet for an obsolete device? You might find a datasheet somewhere, but how can you be sure that it precisely mathches &lt;b&gt;the actual chip&amp;lt;&amp;gt;/b&amp;gt; that you have in your hand?&lt;/b&gt;&lt;/i&gt;&lt;br /&gt;
One of the problems with this &lt;b&gt;antique&lt;/b&gt; is that there is no such thing as &lt;b&gt;an&lt;/b&gt; 8255.  Every version (manufacturer/letters in addition to 8255) will have subtle differences from the other.&lt;br /&gt;
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Are you making something from a book by an author that is too lazy to update to current technology?&lt;br /&gt;
&lt;br /&gt;
or are you in school being taught by an instructor that is too lazy to update to current technology?&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
Erik&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: inforamtion about 8255 interfacing with 8051 microcontrollers</title><link>https://community.arm.com/thread/87520?ContentTypeID=1</link><pubDate>Mon, 26 Dec 2005 18:46:16 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:fe2f86d6-9e65-47f0-b896-7b50ee75c7aa</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;i&gt;&amp;quot;how to interface 8255 IC with 8051 microcontroller.&amp;quot;&lt;/i&gt;&lt;br /&gt;
&lt;br /&gt;
The same way you&amp;#39;d interface anything to any processor:&lt;br /&gt;
&lt;br /&gt;
&lt;b&gt;1. Read the datasheet for the 8255&lt;/b&gt;&lt;br /&gt;
This will tell you what signals you must provide to the 8255, and the timing requirements for them.&lt;br /&gt;
Here you may meet your first problem: where will you find the datasheet for an obsolete device? You might find a datasheet somewhere, but how can you be sure that it precisely mathches the actual chip that you have in your hand?&lt;br /&gt;
&lt;br /&gt;
&lt;b&gt;2. Read the Application Notes &amp;amp; other design support information on the manufacturer&amp;#39;s website&lt;/b&gt;&lt;br /&gt;
Again, this could be tricky.&lt;br /&gt;
The so-called &amp;quot;after market&amp;quot; suppliers are in business to supply obsolete parts to &lt;i&gt;existing&lt;/i&gt; users - they probably do not have the resources to support designing obsolete parts into &lt;i&gt;new&lt;/i&gt; systems!&lt;br /&gt;
&lt;br /&gt;
&lt;b&gt;3. Implement it!&lt;/b&gt;&lt;br /&gt;
You should now have sufficient information to enable you to proceed.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: inforamtion about 8255 interfacing with 8051 microcontrollers</title><link>https://community.arm.com/thread/45285?ContentTypeID=1</link><pubDate>Mon, 26 Dec 2005 05:52:31 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:c5ecfb11-adc8-4db8-be17-b317739340ce</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;Note that the 8255 is obsolete, and has been obsolete for many years.&lt;br /&gt;
&lt;br /&gt;
Why not just choose an 8051 derivative with on-baord flash, and sufficient IO that you don&amp;#39;t &lt;i&gt;need&lt;/i&gt; an 8255...?&lt;br /&gt;
&lt;br /&gt;
&lt;a href="http://www.keil.com/dd/parm_search.asp"&gt;http://www.keil.com/dd/parm_search.asp&lt;/a&gt;&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>