?? funcref-90.html
字號:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"><HTML><HEAD> <META NAME="GENERATOR" CONTENT="LinuxDoc-Tools 0.9.20"> <TITLE>cc65 function reference: Alphabetical function reference: em_map</TITLE> <LINK HREF="funcref-91.html" REL=next> <LINK HREF="funcref-89.html" REL=previous> <LINK HREF="funcref.html#toc3" REL=contents></HEAD><BODY><A HREF="funcref-91.html">Next</A><A HREF="funcref-89.html">Previous</A><A HREF="funcref.html#toc3">Contents</A><HR><H2><A NAME="em_map"></A> 3.49 <A HREF="funcref.html#toc3.49">em_map</A></H2><P><BLOCKQUOTE><DL><DT><B>Function</B><DD><P>Make a page of extended memory accessible.</P><DT><B>Header</B><DD><P><CODE><A HREF="funcref-15.html#em.h">em.h</A></CODE></P><DT><B>Declaration</B><DD><P><CODE>void* __fastcall__ em_map (unsigned page);</CODE></P><DT><B>Description</B><DD><P>The function maps one page of extended memory into linearmemory and returns a pointer to the page frame. Depending on the hardwareand driver, the data is either mapped into the address space or transferedinto a buffer. If you don't need the actual contents of the page (for examplebecause you're going to overwrite it completely, it is better to call<CODE><A HREF="funcref-93.html#em_use">em_use</A></CODE> instead. <CODE>em_use</CODE> will not transfer thedata if it is possible to avoid that.</P><DT><B>Limits</B><DD><P><UL><LI>Calling <CODE>em_map</CODE> will invalidate the memory window, so if youmade any changes to the data in the window, call <CODE><A HREF="funcref-86.html#em_commit">em_commit</A></CODE> first, or the changes are lost.</LI><LI>The function is only available as fastcall function, so it may only beused in presence of a prototype.</LI><LI>The function produces undefined results if no extended memory driver isloaded.</LI></UL></P><DT><B>Availability</B><DD><P>cc65</P><DT><B>See also</B><DD><P><A HREF="funcref-86.html#em_commit">em_commit</A>,<A HREF="funcref-89.html#em_load_driver">em_load_driver</A>,<A HREF="funcref-93.html#em_use">em_use</A></P><DT><B>Example</B><DD><P>None.</P></DL></BLOCKQUOTE></P><HR><A HREF="funcref-91.html">Next</A><A HREF="funcref-89.html">Previous</A><A HREF="funcref.html#toc3">Contents</A></BODY></HTML>?? 快捷鍵說明
復制代碼
Ctrl + C
搜索代碼
Ctrl + F
全屏模式
F11
切換主題
Ctrl + Shift + D
顯示快捷鍵
?
增大字號
Ctrl + =
減小字號
Ctrl + -