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<title>Watara Supervision specific information for cc65
<author><url url="mailto:polluks@sdf.lonestar.org" name="Stefan A. Haubenthal">
<date>2017-11-21

<abstract>
An overview over the Supervision runtime system as it is implemented for the
cc65 C compiler.
</abstract>

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<toc>

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<sect>Overview<p>

This file contains an overview of the Supervision runtime system as it comes
with the cc65 C compiler. It describes the memory layout, Supervision specific header
files, available drivers, and any pitfalls specific to that platform.

Please note that Supervision specific functions are just mentioned here, they are
described in detail in the separate <url url="funcref.html" name="function
reference">. Even functions marked as "platform dependent" may be available on
more than one platform. Please see the function reference for more information.


<sect>Binary format<p>

The standard binary output format generated by the linker for the Supervision target
is a 2&times;16 kbyte machine language program. It is of course
possible to change this behaviour by using one of the different linker configs.

<sect>Memory layout<p>

cc65 generated programs with the default setup run with the I/O area enabled,
which gives a usable memory range of &dollar;8000 - &dollar;FFF9.
More ROM may need additional bankswitching code.

Special locations:

<descrip>
  <tag/Text screen/
<!--  The text screen is located at VRAM &dollar;4000.-->
  No conio support is currently available for the Supervision.

  <tag/Stack/
  The C runtime stack is located at &dollar;1FFF and growing downwards.

  <tag/Heap/
  The C heap is located at the end of the program and grows towards the C
  runtime stack.

</descrip><p>



<sect>Platform specific header files<p>

Programs containing Supervision specific code may use the <tt/supervision.h/ header file.


<sect1>Hardware access<p>

The following pseudo variables declared in the <tt/supervision.inc/ include file do
allow access to hardware located in the address space.

<descrip>

  <tag><tt/IO/</tag>
  The <tt/IO/ defines allow access to the IO chip.

</descrip><p>



<sect>Loadable drivers<p>

<sect1>Graphics drivers<p>

No graphics drivers are currently available for the Supervision.
<!--A TGI driver for the standard graphics mode (160&times;160 in 4 colors) is
available, but must be statically linked, because no file I/O is available.
See the documentation for the <url url="co65.html" name="co65 utility">
for information on how to do that.-->

<sect1>Extended memory drivers<p>

No extended memory drivers are currently available for the Supervision.


<sect1>Joystick drivers<p>

<descrip>

  <tag><tt/supervision-stdjoy.joy (supervision_stdjoy_joy)/</tag>
  A joystick driver for the standard two buttons joypad is available.

</descrip><p>

<sect1>Mouse drivers<p>

No mouse drivers are currently available for the Supervision.


<sect1>RS232 device drivers<p>

No communication port drivers are currently available for the Supervision.



<sect>Limitations<p>

<sect1>Disk I/O<p>

The existing library for the Supervision doesn't implement C file
I/O. There are even no hacks for the <tt/read()/ and <tt/write()/ routines.

To be more concrete, this limitation means that you cannot use any of the
following functions (and a few others):

<itemize>
<item>fclose
<item>fopen
<item>fread
<item>fprintf
<item>fputc
<item>fscanf
<item>fwrite
<item>...
</itemize>



<sect>Other hints<p>



<sect>License<p>

This software is provided 'as-is', without any expressed or implied
warranty.  In no event will the authors be held liable for any damages
arising from the use of this software.

Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:

<enum>
<item>	The origin of this software must not be misrepresented; you must not
	claim that you wrote the original software. If you use this software
	in a product, an acknowledgment in the product documentation would be
	appreciated but is not required.
<item>	Altered source versions must be plainly marked as such, and must not
	be misrepresented as being the original software.
<item>	This notice may not be removed or altered from any source
	distribution.
</enum>

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