SWO 문서 원본 보기

<h2></h2>
<p><strong style="font-size: 14px;"><span style="font-size: large;">Serial Wire Output 란</span></strong></p>
<p><span style="font-size: small;">CoreSight 기반한 chip 에서 2pin debug 통신 프로토콜인 Serial Wire Debug 를 지원할 경우, Serial Wire Output 을 이용하여 1pin trace를 받을 수 있습니다. Serial Wire Debug 신호는 Serial Wire Clock(SWCLK), Serial Wire Data I/O(SWDIO) 이며, JTAG 신호에서 TCK와 TMS 신호 사용합니다.</span></p>
<p>&nbsp; &nbsp; &nbsp;<img src="/data/wiki/2015-05-29/1432873330.png" alt="" /></p>
<p><span style="font-size: small;">총 3pin으로 ITM data를 받아볼 수 있으며 Pin 설정은 10pin일 경우 아래와 같은 pin map을 가질 수 있습니다.</span></p>
<p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<img src="/data/wiki/2015-05-29/1432873336.png" alt="" /></p>
<h2></h2>
<h2></h2>
<h2><strong><span style="font-size: large;">Compiler 적용 방법 (for Cortex-M)</span></strong></h2>
<p><strong><span style="font-size: large;"><br /></span></strong></p>
<p><span style="font-size: small;">1)&nbsp;&nbsp;&nbsp; IAR EWARM</span></p>
<p><span style="font-size: small;">IAR Compiler에서는 SWO Library 제공</span></p>
<p><span style="font-size: small;">Option 적용으로 SWO output 가능</span></p>
<p>&nbsp; &nbsp;<img src="/data/wiki/2015-05-29/1432873361.png" alt="" /></p>
<p>&nbsp;</p>
<p><span style="font-size: small;">2)&nbsp;&nbsp;&nbsp; Keil uVision</span></p>
<p><span style="font-size: small;">SWO trace를 위한 Retargeting 코드가 적용되어야, SWO output 가능</span></p>
&nbsp; 
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="714" valign="top">
<p><span style="font-size: small;">#define ITM_Port8(n)&nbsp;&nbsp;&nbsp; (*((volatile unsigned char   *)(0xE0000000+4*n)))</span></p>
<p><span style="font-size: small;">#define ITM_Port16(n)&nbsp;&nbsp; (*((volatile unsigned   short*)(0xE0000000+4*n)))</span></p>
<p><span style="font-size: small;">#define ITM_Port32(n)&nbsp; &nbsp;(*((volatile unsigned long   *)(0xE0000000+4*n)))</span></p>
<p><span style="font-size: small;">#define DEMCR&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (*((volatile unsigned long   *)(0xE000EDFC)))</span></p>
<p><span style="font-size: small;">#define TRCENA&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0x01000000</span></p>
<p><span style="font-size: small;">/* USER CODE BEGIN PV */</span></p>
<p><span style="font-size: small;">struct __FILE { int handle; /*   Add whatever needed */ };</span></p>
<p><span style="font-size: small;">FILE __stdout;</span></p>
<p><span style="font-size: small;">FILE __stdin;</span></p>
<p><span style="font-size: small;">int fputc(int ch, FILE *f) {</span></p>
<p><span style="font-size: small;">&nbsp;   if (DEMCR &amp; TRCENA) {</span></p>
<p><span style="font-size: small;">&nbsp;&nbsp;&nbsp; while (ITM_Port32(0) == 0);</span></p>
<p><span style="font-size: small;">&nbsp;&nbsp;&nbsp; //ITM_Port32(0) = ch;</span></p>
<p><span style="font-size: small;">ITM_Port8(0)   = ch;</span></p>
<p><span style="font-size: small;">&nbsp;   }</span></p>
<p><span style="font-size: small;">&nbsp;   return(ch);</span></p>
<p><span style="font-size: small;">}</span></p>
</td>
</tr>
</tbody>
</table>
&nbsp;
<h2></h2>
<h2><span style="font-size: large;"><strong>TRACE32 Serial Wire Debug Out(SWO) 설정 및 예시</strong></span></h2>
&nbsp;
<h3><strong><span style="font-size: small;">1)&nbsp;&nbsp;&nbsp; TRACE32 Combiprobe cable</span></strong></h3>
<p><span style="font-size: small;">-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; SWO 1pin trace를 받기 위해서는 TRACE32 Combiprobe cable이 필요합니다. &nbsp;</span></p>
<p>&nbsp; &nbsp; &nbsp;<img src="/data/wiki/2015-05-29/1432873392.png" alt="" /></p>
<h3></h3>
<h3><strong><span style="font-size: small;">2)&nbsp;&nbsp;&nbsp; Serial Wire Debug Port (SWDP) Powerview 설정 명령어</span></strong></h3>
<p><strong><span style="font-size: small;"><br /></span></strong></p>
<p>&nbsp;<span style="font-size: small;">①&nbsp;&nbsp;&nbsp; &nbsp;SWDP 통신 연결 설정</span></p>
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="730" valign="top">
<p><span style="font-size: small;"><strong>SYStem.CONFIG SWDP ON</strong></span></p>
<p><span style="font-size: small;"><strong>SYStem.Up</strong></span></p>
</td>
</tr>
</tbody>
</table>
&nbsp;
<p><span style="font-size: small;">②&nbsp;&nbsp;&nbsp; TPIU pin을 Serial Wire Viewer mode의 ITM trace를 위한 ETM off설정</span></p>
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="730" valign="top">
<p><span style="font-size: small;"><strong>ETM.OFF</strong></span></p>
</td>
</tr>
</tbody>
</table>
&nbsp; &nbsp;
<p><span style="font-size: small;">③&nbsp;&nbsp;&nbsp; &nbsp;Port size와 ITM 설정,</span></p>
<p><span style="font-size: small;">&nbsp;비동기적인 Serial Wire Output 신호는 CPU frequency에 받음에 따라 bit rate를 조정 가능</span></p>
<p><span style="font-size: small;">&agrave; NRZ/2 는 CPU frequency를 둘로 나눌 경우</span></p>
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="730" valign="top">
<p><span style="font-size: small;"><strong>ITM.PortSize SWV</strong></span></p>
<p><span style="font-size: small;"><strong>ITM.PortMode &lt;format&gt;</strong></span></p>
</td>
</tr>
</tbody>
</table>
&nbsp;
<p><span style="font-size: small;">④&nbsp;&nbsp;&nbsp; &nbsp;bit rate를 고정적으로 설정할 경우 (Autofocus나 TraceClock 설정 중 가능)</span></p>
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="730" valign="top">
<p><span style="font-size: small;"><strong>CAnalyzer.TraceCLOCK   &lt;frequency&gt;</strong></span></p>
</td>
</tr>
</tbody>
</table>
&nbsp;
<p><span style="font-size: small;">⑤&nbsp;&nbsp;&nbsp; &nbsp;자동으로 최적의 clock 을 찾는 Autofoucs 기능을 사용할 경우</span></p>
<p><span style="font-size: small;">(Autofocus나 TraceClock 설정 중 가능)</span></p>
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="730" valign="top">
<p><span style="font-size: small;"><strong>CAnalyzer.AutoFocus</strong></span></p>
</td>
</tr>
</tbody>
</table>
&nbsp; &nbsp;
<h3><strong><span style="font-size: small;">3)&nbsp;&nbsp;&nbsp; Printf를 SWO 1pin으로 trace 받을 경우 예시</span></strong></h3>
<p><span style="font-size: small;">printf를 SWO 1pin trace를 이용하여 해당 printf 코드에 해당하는 data를 받아 볼 수 있습니다. &nbsp;</span></p>
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="736" valign="top">
<p><span style="font-size: small;"><strong>SYStem.CONFIG.SWDP   ON</strong></span></p>
<p><span style="font-size: small;"><strong>SYStem.Up</strong></span></p>
<p><span style="font-size: small;"><strong>&nbsp;</strong></span></p>
<p><span style="font-size: small;"><strong>ITM.PortMode   NRZ</strong></span></p>
<p><span style="font-size: small;"><strong>ITM.PortSize   SWV</strong></span></p>
<p><span style="font-size: small;"><strong>CAnalyzer.Init</strong></span></p>
<p><span style="font-size: small;"><strong>CAnalyzer.AutoFocus</strong></span></p>
</td>
</tr>
</tbody>
</table>
<p>&nbsp;</p>
<p>&nbsp;</p>
<p><img src="/data/wiki/2015-05-29/1432873420.png" alt="" /></p>
<p><span style="font-size: small;">문자열 형태로 printf를 받는 것은 현재 구현 중이며, dll파일을 이용하여 해당 data log를 문자열 형태로 확인이 가능합니다.&nbsp;</span></p>
<p>&nbsp;</p>