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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>AT89S52</title><link>https://community.arm.com/developer/tools-software/tools/f/keil-forum/28947/at89s52</link><description> 
Dear Sir, I am having a problem with at89s52 on power up. I am
doing a project which demands serial communication via serial port. I
have gone through one of the threads here, where you had advised one
Mr.Bhagirath to use 3-pin rest(MX810). So, I get</description><dc:language>en-US</dc:language><generator>Telligent Community 10</generator><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/131924?ContentTypeID=1</link><pubDate>Tue, 23 Oct 2012 11:50:21 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:fe55ea89-f629-4f5d-adff-2c70f627a3f8</guid><dc:creator>Jeremy Brookley</dc:creator><description>&lt;p&gt;&lt;p&gt;
Can you post the code you are running? It might help demonstrate
the issue. For instance, if you have an extended delay that you
assumed was in ms but is actually in seconds, it&amp;#39;s possible we could
randomly guess this but it would save a lot of time to see the code
you are working with. Please remember to use the &amp;quot;pre&amp;quot; tags when
posting code (should be described above the text box when posting a
reply).&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/60951?ContentTypeID=1</link><pubDate>Mon, 22 Oct 2012 15:51:32 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:ffcdb38f-7ca1-4374-8885-86fc65272930</guid><dc:creator>rafael belloli</dc:creator><description>&lt;p&gt;&lt;p&gt;
kkjkkkvjchsj,gft&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/143213?ContentTypeID=1</link><pubDate>Thu, 26 Jul 2012 06:56:27 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:21965e16-e752-4c68-8c57-b934c96c1e12</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;the only thing I am asking is that in case after providing the
proper reset arrangement, the problem still persists, what should be
my next step ?&lt;/i&gt;&lt;br /&gt;
with a proper reset supervisor chip, there will be no next step.&lt;/p&gt;

&lt;p&gt;
Erik&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/140325?ContentTypeID=1</link><pubDate>Wed, 25 Jul 2012 19:37:32 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:54875e46-3238-4e0c-ab4d-a93d8faf8e5e</guid><dc:creator>Sujoy BHATTACHARYA</dc:creator><description>&lt;p&gt;&lt;p&gt;
Mr.Malund, I shall not argue that I never believed in proper reset
arrangement but thank you, Sir, that you have made me a bliever in
it. Sir, the only thing I am asking is that in case after providing
the proper reset arrangement, the problem still persists, what should
be my next step ?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/131051?ContentTypeID=1</link><pubDate>Wed, 25 Jul 2012 19:33:51 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:5dfaa9ce-9aa6-4db6-8897-3d4aa3826cb4</guid><dc:creator>Sujoy BHATTACHARYA</dc:creator><description>&lt;p&gt;&lt;p&gt;
No, Sir, I do not have any timer code in my program.I have tried a
code that lights up a LED after 30secs and dims it after another
30secs(blinky), but even this UC does not start functioning properly
on power up. It starts functioning after 1to 2 mins even thought
there is no timer code associated.Could you tell me what is going
wrong?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/136826?ContentTypeID=1</link><pubDate>Wed, 25 Jul 2012 11:52:35 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:6af86e99-7995-441e-a31c-059448070609</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;Do you have a timer running other than the serial setup? The
fact that something times out in 5 to 7 minutes sounds like a timer
not being initialized correctly and after timer overflow the system
appears to run.&lt;/i&gt;&lt;/p&gt;

&lt;p&gt;
since the OP is not a believer in a proper &amp;quot;reset arrangement&amp;quot; I
hold it far more likely that the uC is running garbage as &amp;#39;code&amp;#39; and,
somehow, after a lot of time, something manages to get it going
properly.&lt;/p&gt;

&lt;p&gt;
Erik&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/127638?ContentTypeID=1</link><pubDate>Wed, 25 Jul 2012 10:47:12 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:0d97bcee-5be2-43e3-a5e6-a54c327b356a</guid><dc:creator>doubt that my ISP Al Bradford</dc:creator><description>&lt;p&gt;&lt;p&gt;
Do you have a timer running other than the serial setup? The fact
that something times out in 5 to 7 minutes sounds like a timer not
being initialized correctly and after timer overflow the system
appears to run.&lt;/p&gt;

&lt;p&gt;
Just a far out guess on my part.&lt;/p&gt;

&lt;p&gt;
Bradford&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/131050?ContentTypeID=1</link><pubDate>Wed, 25 Jul 2012 10:26:29 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:e9c68a47-e479-46ec-a699-9eff5f7f1e16</guid><dc:creator>Sujoy BHATTACHARYA</dc:creator><description>&lt;p&gt;&lt;p&gt;
Ok, got your point. I shall do as you have said. Thank you very
very much for giving me your valuable time, Mr.Malund.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/127637?ContentTypeID=1</link><pubDate>Wed, 25 Jul 2012 07:18:19 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:322fa740-a83a-4c8e-bdc4-b02fb87365f6</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;&amp;quot;why do you think specifications are published?&amp;quot;&lt;br /&gt;
what specifications are you talking about, sir?&lt;/i&gt;&lt;br /&gt;
e.g. the specifications of reset in the datasheet AND the rest of
them, spcifications are tere for a purpose, not for your reading
enjoyment.&lt;/p&gt;

&lt;p&gt;
Erik&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/116925?ContentTypeID=1</link><pubDate>Tue, 24 Jul 2012 19:37:30 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:5c8a708d-e619-4130-a339-9bda2e72cab5</guid><dc:creator>Sujoy BHATTACHARYA</dc:creator><description>&lt;p&gt;&lt;p&gt;
Thank you Mr.Malund.&lt;br /&gt;
&amp;quot;does it start at all? after how long?&amp;quot;&lt;br /&gt;
yes, when it starts, it starts immediately without any problem and
performs serial communication. However, sometimes it starts working
after 5mins to 7mins.&lt;/p&gt;

&lt;p&gt;
&amp;quot;why do you think specifications are published?&amp;quot;&lt;br /&gt;
what specifications are you talking about, sir?&lt;/p&gt;

&lt;p&gt;
Sir, I would like to tell you that initially when I had no reset
arrangement, AT89S52 started serial communication without this timing
delay or this anomaly at all. That is why , I have asked whether I
should use reset arrangement at all.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/116927?ContentTypeID=1</link><pubDate>Tue, 24 Jul 2012 19:30:48 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:0516a2da-fb0a-457a-b678-f5dff48b7f46</guid><dc:creator>Sujoy BHATTACHARYA</dc:creator><description>&lt;p&gt;&lt;p&gt;
Thank you Per Westermark for those helping words. I get your
point. So, what you are basically saying is that problem that I have
mentioned may be arising due to my inconsistent reset arrangement.If
this is so, then reset is the first problem that I shall work on. At
the same time,would you please suggest whether I am skipping any
other useful information /point required to solve this problem?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/106207?ContentTypeID=1</link><pubDate>Tue, 24 Jul 2012 12:15:24 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:262eeac6-3c44-4036-b44e-3a92b9259948</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
Hardly any processor can start receiving 8-bit data immediately on
power up. The software normally have to set up baudrate etc for the
UART to know what is expected.&lt;/p&gt;

&lt;p&gt;
Another thing is the state of the line when the UART gets
activated - a character that is sent before the UART is ready will be
lost. So two processors can&amp;#39;t be powered up and expected to be able
to directly talk with each other. First off, there should be a bit of
delay so both are in ready state before communication is activated.
But the communication protocol should also support resends if it is
important that no transfer is missing. How can one side ever know the
other side is ready if there isn&amp;#39;t hw or sw handshaking between
them?&lt;/p&gt;

&lt;p&gt;
But a correct reset solution is vital - lots of state in the
processor that needs to be normalized. That also includes the
interrupt state machines etc. Some of the states can&amp;#39;t be corrected
by the software.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/106210?ContentTypeID=1</link><pubDate>Tue, 24 Jul 2012 12:01:52 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:03431ac0-25c1-42d5-98d8-c80078a38b9b</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;The anomaly I am talking about is that AT89S52 does&amp;#39;nt start
recieving 8bit data immediately on power up&lt;/i&gt;&lt;br /&gt;
does it start at all? after how long?&lt;/p&gt;

&lt;p&gt;
&lt;i&gt;What if I do not use reset arrangement at all for this AT89S52?
Will this fix my problem?&lt;/i&gt;&lt;br /&gt;
why do you think specifications are published?&lt;/p&gt;

&lt;p&gt;
Erik&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/80422?ContentTypeID=1</link><pubDate>Tue, 24 Jul 2012 10:42:33 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:b613b5c2-3cf9-4cdb-9ea5-9c8ad755ed72</guid><dc:creator>Sujoy BHATTACHARYA</dc:creator><description>&lt;p&gt;&lt;p&gt;
Thank you so much sir for those helping words. There is no bug in
the code for sure. The anomaly I am talking about is that AT89S52
does&amp;#39;nt start recieving 8bit data immediately on power up. But this
does not happen always. Sometimes, it works perfectly on power up
with no problem whatsoever. So, what can be other sources of this
anomaly. What if I do not use reset arrangement at all for this
AT89S52? Will this fix my problem?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: AT89S52</title><link>https://community.arm.com/thread/67612?ContentTypeID=1</link><pubDate>Tue, 24 Jul 2012 07:38:12 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:105f7353-c022-4e9d-9dc9-a54c0643eca9</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
&amp;quot;So, what are the other areas from where this anomaly is
rising?&amp;quot;&lt;/p&gt;

&lt;p&gt;
What anomaly?&lt;/p&gt;

&lt;p&gt;
If you have a reset issue, it affects the processor - not just the
UART.&lt;/p&gt;

&lt;p&gt;
If you have just a serial link issue, it is not a reset issue
unless you also have some bug in your code.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>