<?xml version="1.0" encoding="UTF-8" ?>
<?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>DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/developer/tools-software/tools/f/keil-forum/25887/difficulty-in-accessing-mcu-xram</link><description> 
Hi! I&amp;#39;m using Philips P89v51RD2FBC microcontroller. I build my
project using Keil version 2.0. After compilation, total memory
utillization is: 
 Data: 155.2, Xdata: 327, Const: 2062, Code: 23176 

 
Eventhough there is a free memory space in Data as</description><dc:language>en-US</dc:language><generator>Telligent Community 10</generator><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/144742?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 07:56:24 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:be65e09b-4ad7-48e7-8483-4f862eca80cb</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;p&gt;
I&amp;#39;m sorry - you&amp;#39;re right!&lt;/p&gt;

&lt;p&gt;
&lt;a href="http://www.keil.com/dd/chip/3711.htm"&gt;http://www.keil.com/dd/chip/3711.htm&lt;/a&gt;&lt;/p&gt;

&lt;p&gt;
It tells you which &lt;i&gt;header file&lt;/i&gt; to use - not which startup
file!&lt;/p&gt;

&lt;p&gt;
D&amp;#39;oh!&lt;/p&gt;

&lt;p&gt;
However, when you create a &lt;i&gt;&lt;b&gt;new&lt;/b&gt;&lt;/i&gt; Project in uVision,
and choose your CPU, that will automatically select the appropriate
standard startup file.&lt;/p&gt;

&lt;p&gt;
The list of standard startup files, and instructions on how to
customise them, is here: &lt;a href="http://www.keil.com/support/man/docs/c51/c51_ap_startup.htm"&gt;http://www.keil.com/support/man/docs/c51/c51_ap_startup.htm&lt;/a&gt;&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/144738?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 06:39:37 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:987eb381-22ce-4a11-9017-cd68082f511b</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
&amp;quot;Also as you have mentioned earlier XRAM has to be enabled through
SFR [...]&amp;quot;&lt;/p&gt;

&lt;p&gt;
It is time for you to start look closer at details. Andy did not
say that XRAM _has_ to be enabled. He did write &amp;quot;if your chip
requires [...]&amp;quot;. Notice the conditional &amp;quot;if&amp;quot;.&lt;/p&gt;

&lt;p&gt;
Not all chips needs any configuration to enable XRAM. And _if_
your specific chip needs it, then I would recommend you to read the
datasheet for your specific chip. That document will contain the
relevant information on how to turn on the XRAM. Maybe Keil already
has a startup file with such initialization (IF it is needed), but
you really should read up on your chip, so you know what happens.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/142455?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 05:19:24 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:8fef477d-190b-417c-89b8-cbf9f2b17e77</guid><dc:creator>Kshama Deshmukh</dc:creator><description>&lt;p&gt;&lt;p&gt;
Thank you. I visited the link. But it doesn&amp;#39;t give any information
about which startup file has to be added.&lt;/p&gt;

&lt;p&gt;
Also as you have mentioned earlier XRAM has to be enabled through
SFR, I have already enabled the MCU XRAM by making AUXR SFR 0x00.&lt;/p&gt;

&lt;p&gt;
Could you please help me further as I have stuck just due to
declaration problem.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/139344?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 04:48:47 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:20a7a6c2-95a5-4ed8-ba44-926624d4cb1f</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;p&gt;
Look up your chip in the Keil Database:&lt;/p&gt;

&lt;p&gt;
&lt;a href="http://www.keil.com/dd"&gt;http://www.keil.com/dd&lt;/a&gt;&lt;/p&gt;

&lt;p&gt;
it will recommend a startup file.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/139347?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 04:47:39 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:99a25ebc-a32f-4e93-aaa9-381afd00dce8</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
you are trying to run before you know how to walk, you are trying
to walk before you have learned to crawl. this is a surefire way to
break a leg.&lt;/p&gt;

&lt;p&gt;
WORK THROUGH (I did NOT say &amp;#39;read&amp;#39;) the &amp;quot;Keil getting started
guide&amp;quot; and then come back with the questions you may have then.&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: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/130544?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 04:41:45 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:e375388f-f862-4c05-8c1a-a5b4cba68038</guid><dc:creator>Kshama Deshmukh</dc:creator><description>&lt;p&gt;&lt;p&gt;
Thank you for your reply. I visited the link you have sent.&lt;/p&gt;

&lt;p&gt;
At present, I have added startup.a51 file in my project and I&amp;#39;m
using NXP P89v51RD2FBC microcontroller. So could you please tell me
is it an appropriate file?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/125773?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 04:23:35 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:96218ebe-38d4-4024-b03c-99ffd23e749f</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;p&gt;
You didn&amp;#39;t read that link, did you?&lt;/p&gt;

&lt;p&gt;
That &lt;i&gt;&lt;b&gt;is&lt;/b&gt;&lt;/i&gt; what tells you what you need to know!&lt;/p&gt;

&lt;p&gt;
The only thing to beware of is if your chip requires any specific
configuration to enable the XRAM; eg, writing to some SFR(s).&lt;br /&gt;
If it does, then you need to add that manually in your startup code -
the tools will &lt;i&gt;&lt;b&gt;not&lt;/b&gt;&lt;/i&gt; do this for you automatically!&lt;/p&gt;

&lt;p&gt;
For details of the startup code, see: &lt;a href="http://www.keil.com/support/man/docs/c51/c51_ap_startup.htm"&gt;http://www.keil.com/support/man/docs/c51/c51_ap_startup.htm&lt;/a&gt;&lt;/p&gt;

&lt;p&gt;
You really need to spend some time familiarising yourself with the
&lt;b&gt;manuals&lt;/b&gt;...&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/115290?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 04:03:57 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:58270fdf-a3e6-43c9-9aaf-bdf6d6709c09</guid><dc:creator>Kshama Deshmukh</dc:creator><description>&lt;p&gt;&lt;p&gt;
Do you have any idea how to declare these variables?&lt;br /&gt;
kindly guide me in this matter.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/103492?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 03:51:09 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:ed66023a-5de7-4d1c-806c-e8c159ca746a</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;p&gt;
What makes you say that??&lt;/p&gt;

&lt;p&gt;
&lt;a href="http://www.keil.com/support/man/docs/c51/c51_le_memtypes.htm"&gt;http://www.keil.com/support/man/docs/c51/c51_le_memtypes.htm&lt;/a&gt;&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/77826?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 03:49:04 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:81b73d21-ab14-4faf-b7d9-91ae444c0132</guid><dc:creator>Kshama Deshmukh</dc:creator><description>&lt;p&gt;&lt;p&gt;
So, how do I declare them? the variables in MCU XRAM are needed to
be declared as FAR.&lt;/p&gt;

&lt;p&gt;
Kshama&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: DIFFICULTY IN ACCESSING MCU XRAM</title><link>https://community.arm.com/thread/57021?ContentTypeID=1</link><pubDate>Thu, 08 Oct 2009 03:40:09 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:2b82e2f4-9dcb-4bca-b3bb-80777359f957</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;p&gt;
Why are you declaring them as FAR?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>