📄 glossary.htm
字号:
<p>
<a name="1054120"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>deschedule</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051637"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A <a href="glossary.htm#1051804"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>process</i></font></a> is descheduled when it is not being executed by the CPU and has not been <a href="glossary.htm#1051722"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>interrupted</i></font></a> or <a href="glossary.htm#1051894"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>trapped</i></font></a> by an <a href="glossary.htm#1051656"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>exception handler</i></font></a> but it is capable of being restarted. To deschedule a process is to make it descheduled. </font>
</dl>
</dl></dl>
<p>
<a name="1053596"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>Diagnostic Controller Unit</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1053597"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">ST20 hardware macro-cell which provides fully non-intrusive breakpoints, watchpoints and code tracing.</font>
</dl>
</dl></dl>
<p>
<a name="1051642"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>DMA</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051643"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Direct memory access. A <a href="glossary.htm#1051786"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>peripheral</i></font></a> or external device performs DMA when it reads directly from or writes directly to memory.</font>
</dl>
</dl></dl>
<p>
<a name="1051644"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>DMA peripheral</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051645"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A <a href="glossary.htm#1051786"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>peripheral</i></font></a> with a <a href="glossary.htm#1051642"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>DMA</i></font></a> engine.</font>
</dl>
</dl></dl>
<p>
<a name="1051647"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>double word</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051648"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A 64-bit value, occupying two words.</font>
</dl>
</dl></dl>
<p>
<a name="1051650"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>evaluation stack</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051651"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The <span class=Signal>Areg</span>, <span class=Signal>Breg</span> and <span class=Signal>Creg</span>, which together behave as a stack. The evaluation stack is used for expression evaluation and to hold operands for instructions. The registers cannot be individually addressed, but values can be pushed onto the stack or popped off it.</font>
</dl>
</dl></dl>
<p>
<a name="1051653"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>exception</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051654"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A mechanism for handling events outside the normal program flow. An exception may be an <a href="glossary.htm#1051710"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>interrupt</i></font></a> or a <a href="glossary.htm#1051888"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>trap</i></font></a>. </font>
</dl>
</dl></dl>
<p>
<a name="1051656"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>exception handler</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051657"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The code and data which defines the action when an <a href="glossary.htm#1051653"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>exception</i></font></a> is taken. An exception handler may be a <a href="glossary.htm#1051891"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>trap handler</i></font></a> or an <a href="glossary.htm#1051716"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>interrupt handler</i></font></a>.</font>
</dl>
</dl></dl>
<p>
<a name="1051659"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>exception level</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051660"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The signed integer specifying which <a href="glossary.htm#1051653"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>exception</i></font></a> will be taken, which is the word offset from the base of the <a href="glossary.htm#1051662"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>exception vector table</i></font></a> to the <a href="glossary.htm#1055318"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>descriptor</i></font></a> of the <a href="glossary.htm#1051804"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>process</i></font></a> or <a href="glossary.htm#1051653"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>exception</i></font></a>.</font>
</dl>
</dl></dl>
<p>
<a name="1051662"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>exception vector table</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051663"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The table mapping <a href="glossary.htm#1051659"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>exception level</i></font></a>s to user <a href="glossary.htm#1051804"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>process</i></font></a>es and <a href="glossary.htm#1051653"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>exception</i></font></a> <a href="glossary.htm#1055318"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>descriptor</i></font></a>s.</font>
</dl>
</dl></dl>
<p>
<a name="1051665"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>executing</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051666"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A <a href="glossary.htm#1051804"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>process</i></font></a> is executing if the CPU is currently modifying its <a href="glossary.htm#1051867"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>state</i></font></a>. Only one process can be executing at any one time.</font>
</dl>
</dl></dl>
<p>
<a name="1051668"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>external interrupt</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051669"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">An <a href="glossary.htm#1051710"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>interrupt</i></font></a> generated by a <a href="glossary.htm#1051786"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>peripheral</i></font></a> or external device, routed through the <a href="glossary.htm#1051713"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>interrupt controller</i></font></a> and handled by an <a href="glossary.htm#1051716"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>interrupt handler</i></font></a>.</font>
</dl>
</dl></dl>
<p>
<a name="1051671"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>function</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051672"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A named section of code which may have parameters and may return one or more values. </font>
<dt> <a name="1055323"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A primary instruction.</font>
</dl>
</dl></dl>
<p>
<a name="1051677"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>function code</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051678"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The most significant 4-bits of an <a href="glossary.htm#1051695"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>instruction component</i></font></a>, which defines the action of the component. </font>
</dl>
</dl></dl>
<p>
<a name="1051680"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>half-word</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051681"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A 16-bit value or location.</font>
</dl>
</dl></dl>
<p>
<a name="1051683"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>half-word aligned</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051684"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">An address is half-word aligned if it is divisible by two, that is, if bit 0 is 0.</font>
</dl>
</dl></dl>
<p>
<a name="1051686"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>Idle</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051687"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The CPU is idle when there is no <a href="glossary.htm#1051804"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>process</i></font></a> or <a href="glossary.htm#1051656"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>exception handler</i></font></a> <a href="glossary.htm#1051665"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>executing</i></font></a>.</font>
</dl>
</dl></dl>
<p>
<a name="1051689"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>inactive</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051690"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A <a href="glossary.htm#1051804"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>process</i></font></a> is inactive if it is capable of being restarted but it is currently waiting for some event to occur before it can continue. The event might be a <a href="glossary.htm#1051840"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>semaphore</i></font></a> signal or a <a href="glossary.htm#1051786"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>peripheral</i></font></a> completing a <a href="glossary.htm#1051642"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>DMA</i></font></a>.</font>
</dl>
</dl></dl>
<p>
<a name="1051692"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>instruction</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051693"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A code element corresponding to a single instruction set mnemonic, consisting of zero or more <a href="glossary.htm#1051792"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>prefix</i></font></a>es followed by a non-prefix <a href="glossary.htm#1051695"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>instruction component</i></font></a>.</font>
</dl>
</dl></dl>
<p>
<a name="1051695"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>instruction component</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051696"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A single byte of code, consisting of a function code and four bits of data.</font>
</dl>
</dl></dl>
<p>
<a name="1051698"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>instruction data value</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051699"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The operand of a <a href="glossary.htm#1051795"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>primary instruction</i></font></a>, which is built from the least significant four bits of each of the <a href="glossary.htm#1051695"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>instruction component</i></font></a> of the instruction. </font>
</dl>
</dl></dl>
<p>
<a name="1051701"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>instruction pointer</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1054281"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The 32-bit CPU register which holds the address of the next <a href="glossary.htm#1051692"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>instruction</i></font></a> to be executed by the <a href="glossary.htm#1051627"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>current process</i></font></a>.</font>
</dl>
</dl></dl>
<p>
<a name="1054289"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>integer</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1054290"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A whole number, which may be positive, negative or zero.</font>
</dl>
</dl></dl>
<p>
<a name="1051707"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>internal memory</b></font>
<br>
<dl><dl> <dl>
<dt> <a name="1051708"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><a href="glossary.htm#1051774"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>on-chip memory</i></font></a>.</font>
</dl>
</dl></dl>
<p>
<a name="1051710"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif"><b>interrupt</b></font>
<br>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -