mirror of
https://github.com/cc65/cc65.git
synced 2024-12-22 12:30:41 +00:00
Add CARTSIZE to cfg file for configuring the a78 header. Add descriptions of usage.
This commit is contained in:
parent
cc9535e82f
commit
eb86bc33b9
@ -1,7 +1,12 @@
|
||||
# Atari VCS 7800 linker configuration file for cc65
|
||||
# This cfg file adds the a78 header in front of the image
|
||||
# If you want just the ROM you can mark the __EXEHDR__ as weak instead of import
|
||||
# But for the most common use we add the a78 automatically as it
|
||||
# contains info about what kind of cart the build supports
|
||||
|
||||
SYMBOLS {
|
||||
__STACKSIZE__: type = weak, value = $0010; # 16 bytes stack
|
||||
__STACKSIZE__: type = weak, value = $0600; # C stack
|
||||
__CARTSIZE__: type = weak, value = $c000;
|
||||
__EXEHDR__: type = import;
|
||||
__VEC_BOTTOM__: value = $fffa, type = export;
|
||||
__VEC_SIZE__: value = $6, type = export;
|
||||
@ -37,7 +42,7 @@ MEMORY {
|
||||
|
||||
SEGMENTS {
|
||||
ZEROPAGE: load = ZP, type = zp;
|
||||
EXEHDR: load = HEADER, type = ro, define = yes;
|
||||
EXEHDR: load = HEADER, type = ro;
|
||||
STARTUP: load = ROMS, type = ro, define = yes;
|
||||
ONCE: load = ROMS, type = ro, define = yes;
|
||||
CODE: load = ROM, type = ro, define = yes;
|
||||
|
@ -24,7 +24,29 @@ comes with the cc65 C compiler. It describes the memory layout, Atari
|
||||
<sect>Binary format<p>
|
||||
|
||||
The default binary output format generated by the linker for the Atari
|
||||
7800 target is a 32K cartridge image.
|
||||
7800 target is a 48K cartridge image.
|
||||
|
||||
<sect>A78 header<p>
|
||||
|
||||
There is lots of different cart hardware available for the atari7800.
|
||||
Some carts have ROM, RAM, sound hardware, non-volatile high score chips.
|
||||
In order to know what kind of hardware the cart build requires there is
|
||||
a header file of 128 bytes in front of the binary.
|
||||
|
||||
The default build creates a cart file for a 48K rom cart without any
|
||||
extra features like the pokey audio chip or extra RAM.
|
||||
|
||||
In order to make cc65 more user friendly the build will add the a78
|
||||
header automatically. This allows you to run the binary on emulators
|
||||
and flash carts on the real console.
|
||||
|
||||
<sect>Encryption<p>
|
||||
|
||||
In order to boot the game in a mode that supports atari7800 functions
|
||||
the cart must be encrypted after the linking phase.
|
||||
There is a program called sign7800 that can be used to sign the cart.
|
||||
The encryption is not required for running the cart on emulators.
|
||||
You can also run atari2600 games without encryption.
|
||||
|
||||
<sect>Memory layout<p>
|
||||
|
||||
@ -104,12 +126,6 @@ There are no drivers for the Atari 7800.
|
||||
TBD
|
||||
|
||||
|
||||
<sect>Encryption<p>
|
||||
|
||||
In order to boot the game in a mode that supports atari7800 functions
|
||||
the cart must be encrypted after the linking phase.
|
||||
There is a program called sign7800 that can be used to sign the cart.
|
||||
|
||||
<sect>Other hints<p>
|
||||
|
||||
One may write a custom linker configuration file to tune the memory
|
||||
|
@ -4,7 +4,7 @@
|
||||
; This header contains data for emulators
|
||||
;
|
||||
.export __EXEHDR__: absolute = 1
|
||||
|
||||
.import __CARTSIZE__
|
||||
; ------------------------------------------------------------------------
|
||||
; EXE header
|
||||
.segment "EXEHDR"
|
||||
@ -12,7 +12,7 @@
|
||||
.byte 'A','T','A','R','I','7','8','0','0',' ',' ',' ',' ',' ',' ',' '
|
||||
.byte 'G','a','m','e',' ','n','a','m','e',0,0,0,0,0,0,0
|
||||
.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
|
||||
.byte 0,0,$80,0 ; Size
|
||||
.byte 0,0,>__CARTSIZE__,0 ; Set the cart size in the cfg file
|
||||
; bit 0 - pokey at 4000
|
||||
; bit 1 - supergame bank switched
|
||||
; bit 2 - supergame ram at $4000
|
||||
|
Loading…
Reference in New Issue
Block a user