From 9ead405938848f3ff8b1f4a8450dcd21e6bc68ec Mon Sep 17 00:00:00 2001 From: Christian Groessler Date: Wed, 15 Nov 2017 00:13:06 +0100 Subject: [PATCH] Creativision documentation enhancements. --- doc/creativision.sgml | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/doc/creativision.sgml b/doc/creativision.sgml index 64623b3b2..29653ce0f 100644 --- a/doc/creativision.sgml +++ b/doc/creativision.sgml @@ -4,7 +4,7 @@ VTech Creativision (aka Funvision) specific information for cc65 <author><url url="mailto:polluks+cc65@sdf.lonestar.org" name="Stefan A. Haubenthal"> -<date>2016-04-14 +<date>2017-11-15 <abstract> An overview over the Creativision runtime system as it is implemented for the @@ -31,14 +31,16 @@ 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 Creativision target -is a 4 kbyte machine language program. It is of course possible to change -this behaviour by using one of the different linker configs. +is a 4 KB ROM image. To create an 8 KB ROM a custom linker script has +to be used. <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 $B000 - $BEFF. -More ROM may need additional bankswitching code. +cc65 generated programs with the default setup are 4 KB in size, +occupying $B000 - $BFFF. Usable memory space for the +user program is $B000 - $BEFF. $BF00 - +$BFFF is reserved for the runtime and cartridge configuration +area. Special locations: @@ -47,11 +49,15 @@ Special locations: The text screen is located at VRAM $1000. <tag/Stack/ - The C runtime stack is located at $3FF and growing downwards. + The C runtime stack is located at $03FF and growing downwards. + + <tag/RAM/ + The available RAM for cc65 programs of an unexpanded Creativision + starts at $01FA and ends at $03FF. <tag/Heap/ - The C heap is located at the end of the program and grows towards the C - runtime stack. + The C heap is located at the end of the program's data area and + grows towards the C runtime stack. </descrip><p>