bslathi19/cc65
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Updated to the level of apple2.sgml

Browse Source 
git-svn-id: svn://svn.cc65.org/cc65/trunk@4354 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
ol.sc
2009-10-10 11:32:38 +00:00
parent 6a72d53355
commit 90a3e1fa8b
1 changed files with 221 additions and 55 deletions
Download Patch File Download Diff File Expand all files Collapse all files

276
doc/apple2enh.sgml
View File

@@ -2,9 +2,9 @@
<article> <article>
<title>enhanced&nbsp;Apple&nbsp;//e specific information for cc65 <title>Enhanced&nbsp;Apple&nbsp;//e specific information for cc65
<author>Ullrich von Bassewitz, <htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org"> <author>Oliver Schmidt, <htmlurl url="mailto:ol.sc@web.de" name="ol.sc@web.de">
<date>2003-12-16 <date>2009-10-07
<abstract> <abstract>
An overview over the enhanced&nbsp;Apple&nbsp;//e runtime system as it is An overview over the enhanced&nbsp;Apple&nbsp;//e runtime system as it is
@@ -33,48 +33,32 @@ more information.
<sect>Binary format<p> <sect>Binary format<p>
The standard binary output format generated by the linker for the The standard binary file format generated by the linker for the
enhanced&nbsp;Apple&nbsp;//e target is a machine language program with a 4 byte DOS enhanced&nbsp;Apple&nbsp;//e target is a binary program with a 4 byte DOS 3.3 header
3.3 header containing the load address and load size. The standard load address containing the load address and load length. The default load address is
is &dollar;803. &dollar;803.
The DOS 3.3 header is in its own segment named <tt/EXEHDR/. If you don't want
the header for some reason, you can change
<verb>
HEADER: start = $0000, size = $0004, file = %O;
</verb>
to
<verb>
HEADER: start = $0000, size = $0004, file = "";
</verb>
in the linker configuration to have the linker remove it.
<bf/AppleCommander 1.3.5/ or later (available at <url <bf/AppleCommander 1.3.5/ or later (available at <url
url="http://applecommander.sourceforge.net/">) includes an option <tt/-cc65/ url="http://applecommander.sourceforge.net/">) includes the option <tt/-cc65/
that allows to put binary files with the DOS 3.3 header onto disk images that allows to put binary files with a DOS 3.3 header onto disk images
containing either DOS 3.3 or ProDOS 8. containing DOS 3.3 as well as ProDOS 8.
Please note that there is an <bf/Apple&nbsp;&rsqb;&lsqb; ProDOS 8 system program
for loading binary programs/ available in the cc65 User Contributions section.
It adds all benefits of a ProDOS 8 system program to the standard binary
program generated by the linker for the enhanced&nbsp;Apple&nbsp;//e target.
For ProDOS 8 system programs the load address is fixed to &dollar;2000 so there
is no need for a header. Thus the linker configuration
<htmlurl url="apple2enh-4.html#ss4.3" name="apple2enh-system.cfg"> for those programs
omits the DOS 3.3 header. The right AppleCommander option to put system files
without a header on a ProDOS 8 disk image is </-p/.
<sect>Memory layout<p> <sect>Memory layout<p>
In the standard setup, cc65 generated programs use the memory from In the standard setup, cc65 generated programs use the memory from
&dollar;803 to &dollar;95FF, so 35.5KB of RAM are available. While running &dollar;803 to &dollar;95FF, so 35.5 KB of RAM are available.
<tt/main()/ the Language Card bank 2 is enabled for read access. However while
running module constructors/destructors the Language Card is disabled.
Special locations: Special locations:
<descrip> <descrip>
<tag/Stack/ <tag/Stack/
The C runtime stack is located at HIMEM and grows downwards, regardless of The C runtime stack is located at HIMEM and grows downwards, regardless of
how your linker config file is setup. how your linker config file is setup.
@@ -82,33 +66,215 @@ Special locations:
<tag/Heap/ <tag/Heap/
The C heap is located at the end of the program and grows towards the C The C heap is located at the end of the program and grows towards the C
runtime stack. runtime stack.
</descrip><p> </descrip><p>
Enabling the Language Card allows to use it as additional memory for executable While running <tt/main()/ the Language Card bank 2 is enabled for read access.
code. Actually doing so requires either to compile code with the option However while running module constructors/destructors the Language Card is disabled.
<tt/--code-name HIGHCODE/ or to use <tt/#pragma codeseg ("HIGHCODE")/.
The amount of memory available in the Language Card for executable code depends Enabling the Language Card allows to use it as additional memory for cc65
on the chosen program environment. A plain vanilla ProDOS 8 doesn't actually generated code. However code is never automatically placed there. Rather code
use the Language Card bank 2 memory from &dollar;D400 to &dollar;DFFF. needs to be explicitly placed in the Language Card either per file by compiling
Therefore the builtin linker configuration defines these 3KB as <tt/LC/ memory with <tt/--code-name HIGHCODE/ or per function by enclosing in <tt/#pragma
area for executable code. codeseg (push, "HIGHCODE")/ and <tt/#pragma codeseg (pop)/. In either case the
cc65 runtime system takes care of actually moving the code into the Language
Card.
A plain vanilla DOS 3.3 doesn't make use of the Language Card at all. So you The amount of memory available in the Language Card for generated code depends
can change on the chosen <htmlurl url="apple2enh-4.html" name="linker configuration">.
<verb>
LC: start = $D400, size = $0C00, define = yes;
</verb>
to
<verb> <sect>Linker configurations<p>
LC: start = $D000, size = $3000, define = yes;
</verb>
in the linker configuration to define the whole 12KB Language Card address The ld65 linker comes with a builtin config file for the enhanced&nbsp;Apple&nbsp;//e,
space as memory area for executable code. which is used via <tt/-t apple2enh/ (and displayed via <tt/--dump-config apple2enh/).
The apple2enh package comes with additional secondary linker config files, which
are used via <tt/-C &lt;configfile&gt;/.
<sect1>builtin config file<p>
Default configuration optimized for a binary program running on ProDOS 8 with
BASIC.SYSTEM. A plain vanilla ProDOS 8 doesn't actually use the Language Card
bank 2 memory from &dollar;D400 to &dollar;DFFF.
<descrip>
<tag><tt/RAM:/ Main memory area</tag>
From &dollar;803 to &dollar;95FF (35.5 KB)
<tag><tt/LC:/ Language Card memory area</tag>
From &dollar;D400 to &dollar;DFFF (3 KB)
<tag><tt/STARTADDRESS:/ Program start address</tag>
Variable (default: &dollar;803)
<tag><tt/HEADER:/ Binary file header</tag>
DOS 3.3 header (address and length)
</descrip><p>
<sect1><tt/apple2enh-dos33.cfg/<p>
Configuration optimized for a binary program running on DOS 3.3. A plain
vanilla DOS 3.3 doesn't make use of the Language Card at all.
<descrip>
<tag><tt/RAM:/ Main memory area</tag>
From &dollar;803 to &dollar;95FF (35.5 KB)
<tag><tt/LC:/ Language Card memory area</tag>
From &dollar;D000 to &dollar;FFFF (12 KB)
<tag><tt/STARTADDRESS:/ Program start address</tag>
Variable (default: &dollar;803)
<tag><tt/HEADER:/ Binary file header</tag>
DOS 3.3 header (address and length)
</descrip><p>
<sect1><tt/apple2enh-system.cfg/<p>
Configuration for a system program running on ProDOS 8.
<descrip>
<tag><tt/RAM:/ Main memory area</tag>
From &dollar;2000 to &dollar;BEFF (39.75 KB)
<tag><tt/LC:/ Language Card memory area</tag>
From &dollar;D400 to &dollar;DFFF (3 KB)
<tag><tt/STARTADDRESS:/ Program start address</tag>
Fixed (&dollar;2000)
<tag><tt/HEADER:/ Binary file header</tag>
None
</descrip><p>
<sect1><tt/apple2enh-loader.cfg/<p>
Configuration optimized for a binary program running on ProDOS 8 without
BASIC.SYSTEM. Intended to be used with <bf/LOADER.SYSTEM - an
Apple&nbsp;&rsqb;&lsqb; ProDOS 8 loader for cc65 programs/, which is available
in the cc65 User Contributions section.
A program loaded by LOADER.SYSTEM works like a ProDOS 8 system program but
isn't tied to the start adress &dollar;2000. Thus with the default start
address &dollar;800 the main memory area is increased by 6 KB.
<descrip>
<tag><tt/RAM:/ Main memory area</tag>
From &dollar;800 to &dollar;BEFF (45.75 KB)
<tag><tt/LC:/ Language Card memory area</tag>
From &dollar;D400 to &dollar;DFFF (3 KB)
<tag><tt/STARTADDRESS:/ Program start address</tag>
Variable (default: &dollar;800)
<tag><tt/HEADER:/ Binary file header</tag>
DOS 3.3 header (address and length)
</descrip><p>
<sect1><tt/apple2enh-reboot.cfg/<p>
Configuration optimized for a binary program running on ProDOS 8 without
BASIC.SYSTEM. Intended to be used with <bf/LOADER.SYSTEM - an
Apple&nbsp;&rsqb;&lsqb; ProDOS 8 loader for cc65 programs/ (see above) together
with the function <tt/rebootafterexit()/.
If a ProDOS 8 system program doesn't quit to the ProDOS 8 dispatcher but rather
reboots the machine after exit then a plain vanilla ProDOS 8 doesn't make use of
the Language Card bank 2 at all.
This setup makes nearly 50 KB available to a cc65 program - on a 64 KB machine!
<descrip>
<tag><tt/RAM:/ Main memory area</tag>
From &dollar;800 to &dollar;BEFF (45.75 KB)
<tag><tt/LC:/ Language Card memory area</tag>
From &dollar;D000 to &dollar;DFFF (4 KB)
<tag><tt/STARTADDRESS:/ Program start address</tag>
Variable (default: &dollar;800)
<tag><tt/HEADER:/ Binary file header</tag>
DOS 3.3 header (address and length)
</descrip><p>
<sect>ProDOS 8 system programs<p>
ProDOS 8 system programs are always loaded to the start adress &dollar;2000.
For cc65 programs this means that the 6 KB from &dollar;800 to &dollar;2000 are
by default unused. There are however several options to make use of that memory
range.
<sect1>LOADER.SYSTEM<p>
The easiest (and for really large programs in fact the only) way to have a cc65
program use the memory from &dollar;800 to &dollar;2000 is to link it as binary
(as opposed to system) program using the linker configuration
<htmlurl url="apple2enh-4.html#ss4.4" name="apple2enh-loader.cfg"> with start address
&dollar;800 and load it with <bf/LOADER.SYSTEM - an Apple&nbsp;&rsqb;&lsqb;
ProDOS 8 loader for cc65 programs/. The program then works like a system program
(i.e. quits to the ProDOS dispatcher).
Using LOADER.SYSTEM is as simple as copying it to the ProDOS 8 directory of the
program to load under name &lt;program&gt;.SYSTEM as a system program. For
example the program <tt/MYPROG/ is loaded by <tt/MYPROG.SYSTEM/.
<sect1>Heap<p>
If the cc65 program can be successully linked as system program using the linker
configuration <htmlurl url="apple2enh-4.html#ss4.3" name="apple2enh-system.cfg"> but
uses the heap either explicitly or implicitly (i.e. by loading a driver) then
the memory from &dollar;800 to &dollar;2000 can be added to the heap by calling
<tt/_heapadd ((void *) 0x0800, 0x1800);/ at the beginning of <tt/main()/.
<sect1>ProDOS 8 I/O buffers<p>
ProDOS 8 requires for every open file a page-aligned 1 KB I/O buffer. By default
these buffers are allocated by the cc65 runtime system on the heap using
<tt/posix_memalign()/. While this is generally the best solution it means quite
some overhead for (especially rather small) cc65 programs which do open files
but don't make use of the heap otherwise.
The apple2enh package comes with the alternative ProDOS 8 I/O buffer allocation
module <tt/apple2enh-iobuf-0800.o/ which uses the memory between &dollar;800 and
the program start address for the 1 KB I/O buffers. For system programs (with
start address &dollar;2000) this results in up to 6 I/O buffers and thus up to 6
concurrently open files.
While using <tt/_heapadd()/ as described in the section above together with the
default I/O buffer allocation basically yields the same placement of I/O buffers
in memory the primary benefit of <tt/apple2enh-iobuf-0800.o/ is a reduction in code
size - and thus program file size - of more than 1400 bytes.
Using <tt/apple2enh-iobuf-0800.o/ is as simple as placing it on the linker command
line like this:
<tscreen><verb>
cl65 -t apple2enh -C apple2enh-system.cfg myprog.c apple2enh-iobuf-0800.o
</verb></tscreen>
@@ -118,7 +284,7 @@ Programs containing enhanced&nbsp;Apple&nbsp;//e specific code may use the
<tt/apple2enh.h/ header file. <tt/apple2enh.h/ header file.
<sect1>enhanced&nbsp;Apple&nbsp;//e specific functions<p> <sect1>Enhanced&nbsp;Apple&nbsp;//e specific functions<p>
The functions listed below are special for the enhanced&nbsp;Apple&nbsp;//e. See The functions listed below are special for the enhanced&nbsp;Apple&nbsp;//e. See
the <htmlurl url="funcref.html" name="function reference"> for declaration and the <htmlurl url="funcref.html" name="function reference"> for declaration and
@@ -158,7 +324,7 @@ you cannot do it, it just means that there's no help.
<tt/--start-addr $6000/ to reserve both hires pages. <tt/--start-addr $6000/ to reserve both hires pages.
In memory constrained situations the memory from &dollar;803 to &dollar;1FFF In memory constrained situations the memory from &dollar;803 to &dollar;1FFF
can be made available to a program by executing <tt/_heapadd ((void *) 0x0803, 0x17FD);/ can be made available to a program by calling <tt/_heapadd ((void *) 0x0803, 0x17FD);/
at the beginning of <tt/main()/. Doing so is beneficial even if the program at the beginning of <tt/main()/. Doing so is beneficial even if the program
doesn't use the the heap explicitly because loading the driver (and in fact doesn't use the the heap explicitly because loading the driver (and in fact
already opening the driver file) uses the heap implicitly. already opening the driver file) uses the heap implicitly.
@@ -257,7 +423,7 @@ BASIC.SYSTEM) there are some limitations for DOS 3.3:
Although <htmlurl url="dio.html" name="DIO"> generally works with all ProDOS 8 Although <htmlurl url="dio.html" name="DIO"> generally works with all ProDOS 8
devices, the function <htmlurl url="dio-3.html" name="dio_query_sectcount()"> devices, the function <htmlurl url="dio-3.html" name="dio_query_sectcount()">
simply always return 280 (which is only correct for a 140KB disk). simply always return 280 (which is only correct for a 140 KB disk).
<sect1>Direct console I/O<p> <sect1>Direct console I/O<p>