1 <!doctype linuxdoc system>
4 <title>PC-Engine (TurboGrafx 16) System-specific information for cc65
5 <author><url url="mailto:groepaz@gmx.net" name="Groepaz/Hitmen">,<newline>
6 <url url="mailto:greg.king5@verizon.net" name="Greg King">
9 An overview over the PCE runtime system as it is implemented for the
13 <!-- Table of contents -->
16 <!-- Begin the document -->
20 This file contains an overview of the PCE runtime system as it comes
21 with the cc65 C compiler. It describes the memory layout, PCE-specific header
22 files, available drivers, and any pitfalls specific to that platform.
24 Please note that PCE-specific functions are just mentioned here; they are
25 described, in detail, in the separate <url url="funcref.html" name="function
26 reference">. Even functions marked as "platform dependent" might be available on
27 more than one platform. Please see the function reference for more
32 <sect>Binary format<p>
34 The binary output file generated by the linker, for the PCE target, is an
35 image, with no header, that has 8K bytes in the wrong place. That file must be
36 post-processed; the 8K at the end must be moved to the front of the image.
38 On POSIX systems, the <tt/dd/ command and the shell give a convenient way to do
39 it. Here is an example of their use:
41 dd if=conio.bin bs=8K skip=3 > conio.pce
42 dd if=conio.bin bs=8K count=3 >> conio.pce
44 The first command grabs the last 8K of a 32K file, and writes it as the first
45 part of a new file. The second command reads all but the last part of the old
46 file, and appends it to the new file.
48 +--------+--------+--------+--------+
49 | Bank 1 | Bank 2 | Bank 3 | Bank 0 | <-- "conio.bin"
50 +--------+--------+--------+--------+
52 +--------+--------+--------+--------+
53 | Bank 0 | Bank 1 | Bank 2 | Bank 3 | <-- "conio.pce"
54 +--------+--------+--------+--------+
56 <em/Note/: That <tt/.pce/ file shows the format of the ROM cartridge that is
57 plugged into a PC-Engine. But, that <tt/.bin/ file shows what programs
58 actually see when they execute the code in that cartridge.
62 <sect>Memory layout<p>
64 cc65-generated programs with the default setup run with the memory map that was
65 used by many PC-Engine games:
67 <item>The first 8K bytes is the I/O area.
68 <item>The second 8K bytes is RAM, which holds
70 <item>the redirected zero-page and the redirected hardware stack page,
71 <item>and 7680 bytes of general memory ($2200 - $3FFF).
73 <item>The last 8K bytes in the usual 64K-byte range is the ROM that holds the
80 <tag/Text screen and Font/
81 The text screen is located at Video RAM (VRAM) address $0000;
82 the Font is located at VRAM address $2000.
85 The C run-time stack is located in system RAM at $3FFF;
89 The Data (initialized variables) and BSS (uninitialized variables) sections are
90 placed one after the other into system RAM at $2200.
93 The C heap is located after the end of the BSS section;
94 and, extends up to the C run-time stack.
97 In an 8K ROM cartridge, code and read-only data are located between
98 $E000 and $FFF5 in the System bank.
100 In a 16K cartridge, code and read-only data are located between $C000
103 In a 32K cartridge, code and read-only data are located between $8000
109 <sect>Platform-specific header files<p>
111 Programs containing PCE-specific code may use the <tt/pce.h/ header file.
114 <sect1>PCE-specific functions<p>
117 <item>waitvsync</item>
118 <item>get_tv (since all PCE systems are NTSC, this always returns TV_NTSC)</item>
122 <sect1>Hardware access<p>
124 The following constants, defined in the <tt/pce.inc/ include file, do
125 allow access to hardware that is located in the address space.
130 The <tt/PSG/ defines allow access to the PSG (Programmable Sound Generator).
133 The <tt/VCE/ defines allow access to the VCE chip (Video Color Encoder).
136 The <tt/VDC/ defines allow access to the VDC chip (Video Display Controller).<newline>
137 32K of 16-bit words of Video RAM can be accessed only through this chip.
143 <sect>Loadable drivers<p>
145 All drivers must be statically linked because no file I/O is available.
146 The names in the parentheses denote the symbols to be used for static linking of the drivers.
149 <sect1>Graphics drivers<p>
151 No TGI graphics drivers are currently available for the PCE.
154 <sect1>Extended memory drivers<p>
156 No extended memory drivers are currently available for the PCE.
159 <sect1>Joystick drivers<p>
163 <tag><tt/pce-stdjoy.joy (pce_stdjoy)/</tag>
164 A joystick driver for the standard two-button joypad is available.
166 Note that the Japanese 6-button pad currently is not supported.
171 <sect1>Mouse drivers<p>
173 No mouse drivers are currently available for the PCE.
176 <sect1>RS232 device drivers<p>
178 No serial drivers are currently available for the PCE.
187 The existing library for the PCE doesn't implement C file
188 I/O. There are no hacks for the <tt/read()/ and <tt/write()/ routines.
190 To be more concrete, that limitation means that you cannot use any of the
191 following functions (and a few others):
210 <item><url url="https://mednafen.github.io/" name= "Mednafen"> is a good
211 emulator to use for the PC-Engine.
214 Some useful resources on PCE coding:
217 <item><url url="http://blog.blockos.org/?tag=pc-engine">
218 <item><url url="http://pcedev.blockos.org/viewforum.php?f=5">
219 <item><url url="http://www.romhacking.net/?page=documents&platform=4">
220 <item><url url="http://archaicpixels.com/Main_Page">
222 <item><url url="http://www.magicengine.com/mkit/doc.html">
224 <item><url url="https://github.com/uli/huc">
225 <item><url url="http://www.zeograd.com/parse.php?src=hucf">
232 This software is provided "as-is", without any expressed or implied
233 warranty. In no event will the authors be held liable for any damages
234 arising from the use of this software.
236 Permission is granted to anyone to use this software for any purpose,
237 including commercial applications, and to alter it and redistribute it
238 freely, subject to the following restrictions:
241 <item>The origin of this software must not be misrepresented; you must not
242 claim that you wrote the original software. If you use this software
243 in a product, an acknowledgment in the product documentation would be
244 appreciated, but is not required.
245 <item>Altered source versions must be marked plainly as such; and, must not
246 be misrepresented as being the original software.
247 <item>This notice may not be removed or altered from any source