CPEEK - Revision history

http://wiki.mcselec.com/bavr/index.php?action=history&feed=atom&title=CPEEK CPEEK - Revision history 2026-04-13T16:11:53Z Revision history for this page on the wiki MediaWiki 1.18.6 http://wiki.mcselec.com/bavr/index.php?title=CPEEK&diff=4987&oldid=prev Admin at 20:24, 13 December 2014 2014-12-13T20:24:02Z

<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 20:24, 13 December 2014</td> </tr><tr><td colspan="2" class="diff-lineno">Line 44:</td> <td colspan="2" class="diff-lineno">Line 44:</td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>The code memory is exactly the same as the BIN file that the compiler creates.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>The code memory is exactly the same as the BIN file that the compiler creates.</div></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>So why is Cpeek() useful ? You could read the memory and perform a checksum to see if the code is valid.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>So why is Cpeek() useful<ins class="diffchange diffchange-inline">&nbsp;</ins>? You could read the memory and perform a checksum to see if the code is valid.</div></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Or you could check if a boot loader is present in the code.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Or you could check if a boot loader is present in the code.</div></td></tr> <tr><td colspan="2" class="diff-lineno">Line 59:</td> <td colspan="2" class="diff-lineno">Line 59:</td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Cpeek() is limited to the first 64 KB of the code memory. For processors that have larger flash code memory like the Mega128 (128KB) you can use&nbsp;[[CPEEKH|CpeekH]]().</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Cpeek() is limited to the first 64 KB of the code memory. For processors that have larger flash code memory like the Mega128 (128KB) you can use&nbsp;[[CPEEKH|CpeekH]]().</div></td></tr> <tr><td colspan="2"> </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"> </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"> </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"> </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;">While the AVR uses word addresses since all instructions are 2 bytes long, the Cpeek() function uses a byte address. You need to take that in consideration with for example a boot loader address. The Atmel data sheet will only mention word addresses. For example boot loader address $1000 in the data sheet is $2000 and $2001 byte address for Cpeek().</ins></div></td></tr> <tr><td colspan="2"> </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"> </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 class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><span style="font-family: Arial;">&nbsp;</span></div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><span style="font-family: Arial;">&nbsp;</span></div></td></tr> </table>

Admin http://wiki.mcselec.com/bavr/index.php?title=CPEEK&diff=4694&oldid=prev Admin at 13:26, 4 February 2014 2014-02-04T13:26:34Z

<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 13:26, 4 February 2014</td> </tr><tr><td colspan="2" class="diff-lineno">Line 38:</td> <td colspan="2" class="diff-lineno">Line 38:</td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><span style="font-family: Arial;">&nbsp;</span></div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><span style="font-family: Arial;">&nbsp;</span></div></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del class="diffchange diffchange-inline">There </del>is <del class="diffchange diffchange-inline">no CPOKE statement because you can not write into program </del>memory.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">So what </ins>is <ins class="diffchange diffchange-inline">code </ins>memory<ins class="diffchange diffchange-inline">? Code memory is the same as the flash memory where your program code is stored</ins>.</div></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'>−</td><td style="background: #ffa; color:black; font-size: smaller;"><div>Cpeek(0) will return the first byte of the <del class="diffchange diffchange-inline">file</del>. Cpeek(1) will return the second byte of the <del class="diffchange diffchange-inline">binary file</del>.</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">That is not the same memory as the EEPROM memory!</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">The code memory is exactly the same as the BIN file that the compiler creates.</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">So why is Cpeek() useful ? You could read the memory and perform a checksum to see if the code is valid.</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">Or you could check if a boot loader is present in the code.</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">&nbsp;</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">There is no CPOKE statement because you can not write into program/code memory. Only a boot loader(a piece of code in a special area of the code memory) &nbsp;can write to the normal code memory.</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">&nbsp;</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>Cpeek(0) will return the first byte of the <ins class="diffchange diffchange-inline">flash code memory</ins>. Cpeek(1) will return the second byte of the <ins class="diffchange diffchange-inline">flash code memory.</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">&nbsp;</ins></div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div> </div></td></tr> <tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins class="diffchange diffchange-inline">Cpeek() is limited to the first 64 KB of the code memory. For processors that have larger flash code memory like the Mega128 (128KB) you can use&nbsp;[[CPEEKH|CpeekH]]()</ins>.</div></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr> <tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><span style="font-family: Arial;">&nbsp;</span></div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div><span style="font-family: Arial;">&nbsp;</span></div></td></tr> </table>

Admin http://wiki.mcselec.com/bavr/index.php?title=CPEEK&diff=557&oldid=prev Admin: Created page with "= <span class="f_Header">Action</span> = Returns a byte stored in code memory. <span style="font-family: Arial;"> </span> <span style="font-family: Arial;"> </spa..." 2013-02-08T13:16:58Z

<p>Created page with "= <span class="f_Header">Action</span> = Returns a byte stored in code memory. <span style="font-family: Arial;"> </span> <span style="font-family: Arial;"> </spa..."</p> <p><b>New page</b></p><div>= <span class="f_Header">Action</span> =<br /> <br /> Returns a byte stored in code memory.<br /> <br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> = <span class="f_Header">Syntax</span> =<br /> <br /> var =&nbsp;<span class="f_Syntax">CPEEK</span>( address )<br /> <br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> = <span class="f_Header">Remarks</span> =<br /> <div style="padding: 0px; margin: 0px 0px 0px 4px;"><br /> {| width="604" cellspacing="0" cellpadding="1" border="1" style="border: 2px solid rgb(0, 0, 0); border-spacing: 0px; border-collapse: collapse;"<br /> |- style="vertical-align: top;"<br /> | valign="top" width="17%" style="width: 99px; border: 1px solid rgb(0, 0, 0);" | <br /> Var<br /> <br /> | valign="top" width="100%" style="width: 496px; border: 1px solid rgb(0, 0, 0);" | <br /> Numeric variable that is assigned with the content of the program memory at<br /> <br /> address<br /> <br /> |- style="vertical-align: top;"<br /> | valign="top" width="17%" style="width: 99px; border: 1px solid rgb(0, 0, 0);" | <br /> Address<br /> <br /> | valign="top" width="100%" style="width: 496px; border: 1px solid rgb(0, 0, 0);" | <br /> Numeric variable or constant with the address location<br /> <br /> |}<br /> </div><br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> There is no CPOKE statement because you can not write into program memory.<br /> <br /> Cpeek(0) will return the first byte of the file. Cpeek(1) will return the second byte of the binary file.<br /> <br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> = <span class="f_Header">See also</span> =<br /> <br /> [[PEEK]]&nbsp;,&nbsp;[[POKE]]&nbsp;,&nbsp;[[INP]]&nbsp;,&nbsp;[[OUT]],&nbsp;[[SETREG]],&nbsp;[[GETREG]]<br /> <br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> <span style="font-family: Arial;">&nbsp;</span><br /> <br /> = <span class="f_Header">Example</span> =<br /> <br /> <br/><source lang="bascomavr"><br /> '-----------------------------------------------------------------------------------------<br /> 'name : peek.bas<br /> 'copyright : (c) 1995-2005, MCS Electronics<br /> 'purpose : demonstrates PEEk, POKE, CPEEK, INP and OUT<br /> 'micro : Mega48<br /> 'suited for demo : yes<br /> 'commercial addon needed : no<br /> '-----------------------------------------------------------------------------------------<br /> <br /> $regfile = "m48def.dat" ' specify the used micro<br /> $crystal = 4000000 ' used crystal frequency<br /> $baud = 19200 ' use baud rate<br /> $hwstack = 32 ' default use 32 for the hardware stack<br /> $swstack = 10 ' default use 10 for the SW stack<br /> $framesize = 40 ' default use 40 for the frame space<br /> <br /> Dim I As Integer , B1 As Byte<br /> 'dump internal memory<br /> For I = 0 To 31 'only 32 registers in AVR<br /> B1 = Peek(i) 'get byte from internal memory<br /> Print Hex(b1) ; " ";<br /> 'Poke I , 1 'write a value into memory<br /> Next<br /> Print 'new line<br /> 'be careful when writing into internal memory !!<br /> <br /> 'now dump a part ofthe code-memory(program)<br /> For I = 0 To 255<br /> B1 = Cpeek(i) 'get byte from internal memory<br /> Print Hex(b1) ; " ";<br /> Next<br /> 'note that you can not write into codememory!!<br /> <br /> Out &H8000 , 1 'write 1 into XRAM at address 8000<br /> B1 = Inp(&H8000) 'return value from XRAM<br /> Print B1<br /> End<br /> </source><br/>{{Languages}}<br /> <br /> [[Category:BASCOM Language Reference]]</div>

Admin