+<sect>Extras<p>
+
+<sect1>80 Columns conio driver<p>
+
+The C64 package comes with an alternative software driven 80 columns
+module <tt/c64-soft80.o/ which uses the memory under I/O between $D000
+and $FF3F.
+
+In memory constrained situations the memory from $400 to $7FF
+can be made available to a program by calling <tt/_heapadd ((void *) 0x0400, 0x0400);/
+at the beginning of <tt/main()/. Doing so is beneficial even if the program
+doesn't use the the heap explicitly because loading a driver uses the heap implicitly.
+
+Using <tt/c64-soft80.o/ is as simple as placing it on the linker command
+line like this:
+
+<tscreen><verb>
+cl65 -t c64 myprog.c c64-soft80.o
+</verb></tscreen>
+
+Note that the soft80 conio driver is incompatible with the
+<tt/c64-ram.emd (c64_ram_emd)/ extended memory driver and the
+ <tt/c64-hi.tgi (c64_hi_tgi)/ graphics driver.