When a program starts running, INIT is moved from one place to another place. Then, INIT's code is executed; and, the first place is re-used for variables. After the INIT code has finished, the second place can be re-used by the heap and the C stack. That means that initiation code and data won't waste any RAM space after they stop being needed.
Up to now static drivers were created via co65 from dynamic drivers. However there was an issue with that approach:
The dynamic drivers are "o65 simple files" which obligates that they start with the 'code' segment. However dynamic drivers need to start with the module header - which is written to. For dynamic drivers this isn't more than a conceptual issue because they are always contain a 'data' segment and may therefore only be loaded into writable memory.
However when dynamic drivers are converted to static drivers using co65 then that issue becomes a real problem as then the 'code' segment may end up in non-writable memory - and thus writing to the module header fails.
Instead of changing the way dynamic drivers work I opted to rather make static driver creation totally independent from dynamic drivers. This allows to place the module header in the 'data' segment (see 'module.mac').
This change was suppsed to fix the issue that the former JUMPTABLE is merked as 'ro' while it is actually written to in several scenarios. When drivers are converted using co65 and then compiled into ROMs the JUMPTABLE isn't copied to RAM and therefore the write operations in question fail.
However unfortunately I didn't succeed in changing that :-( Just setting the former JUMPTABLE to 'rw' broke the drivers. So I placed the DATA segment directly after the former JUMPTABLE segment. This made the drivers converted with co65 work again - obviously after changing libsrc/Makefile:235 from '--code-label' to '--data-label'. But the actual dynamic drivers still didn't work as the former JUMPTABLE wasn't placed as the beginning of the loaded file anymore. That effect could be changed by exchanging src/ld65/o65.c:1391 with src/ld65/o65.c:1394 but doing so broke the drivers again :-((
The Apple2 doesn't have sprites so the Apple2 mouse callbacks place a special character on the text screen to indicate the mouse position. In order to support the necessary character removing and redrawing the Apple2 mouse driver called the Apple2 mouse callbacks in an "unusual way". So far so (sort of) good.
However the upcoming Atari mouse driver aims to support both "sprite-type" mouse callbacks as well as "text-char-type" mouse callbacks. Therefore the interface between mouse drivers and callbacks needs to be extended to allow the mouse callbacks to hide their different types from the mouse driver.
The nature of this change can be seen best by looking at the Apple2 file modifications. The CBM drivers and callbacks (at least the current ones) don't benefit from this change.
The mouse reference is a pointer. If it's NULL, the driver uses a default. If it's non-NULL, then it points to a function that the driver can call. That function will adjust the driver's calibration value. It could ask the user to adjust the pen; or, it could read a file that holds a value from a previous calibration.
Application writers can choose how it's done: a function that's provided by the library, a custom function, or nothing.
Occasionally dynamically drivers suffer from not being to refer to
content in the C library. Therefore I added a mechanism to allow
a C library for a certian target to define a symbol that will be
handed over to dynamic drivers for that target. Then the drivers
can use their refernce to that symbol to access content in the C
library.
They use the mouse driver programming interface.
Added a test program for lightpen drivers. Now, it knows about only those two drivers; it will need updating when others are added.
- No complex shell logic.
- "Source file shadowing" for all targets via vpath.
- Dependency handling.
- True incremental build.
- Don't write into source directories.
- Easy cleanup by just removing 'wrk'.
- No complex shell logic.
- "Source file shadowing" for all targets via vpath.
- Dependency handling.
- True incremental build.
- Don't write into source directories.
- Easy cleanup by just removing 'wrk'.
Moved getdevice.s from 'c64'/'c128' to 'cbm' making use of the new 'ST' setup.
git-svn-id: svn://svn.cc65.org/cc65/trunk@5834 b7a2c559-68d2-44c3-8de9-860c34a00d81
named EXEHDR.
* Renamed BASICHDR to EXEHDR for the PET-II machines.
* Moved the call to CHRCH in front of the code that saves the zero page, since
open files are sometimes remembered in the zero page, so we need to close
them before we grab a copy.
git-svn-id: svn://svn.cc65.org/cc65/trunk@4507 b7a2c559-68d2-44c3-8de9-860c34a00d81
* Removed CIRCLE
* Aspect ratio is a new header variable
* Removed the reserved bytes - it's easier to bump the API version
* Clipping is done completely in the wrapper
git-svn-id: svn://svn.cc65.org/cc65/trunk@4396 b7a2c559-68d2-44c3-8de9-860c34a00d81
for the VIC20: PLOT is not an kernal entry but a library function that will
do the right stuff. This makes it work with other stuff that calls PLOT, too.
git-svn-id: svn://svn.cc65.org/cc65/trunk@4249 b7a2c559-68d2-44c3-8de9-860c34a00d81
in the distribution.
Added --forget-inc-paths to the command line of the assembler in the
Makefiles, because the assembler does now have builtin paths and will find
include files from an installation first.
Hopefully fixed any problems that arose from the two changes.
git-svn-id: svn://svn.cc65.org/cc65/trunk@4223 b7a2c559-68d2-44c3-8de9-860c34a00d81
program. The standard driver and mode is the first one in the tgi_mode_table.
git-svn-id: svn://svn.cc65.org/cc65/trunk@4153 b7a2c559-68d2-44c3-8de9-860c34a00d81
main() is encountered. Define this symbol in the startup code. This will
automatically force linking of the startup code which can then reside inside
the standard library as any other object file.
git-svn-id: svn://svn.cc65.org/cc65/trunk@3988 b7a2c559-68d2-44c3-8de9-860c34a00d81
routine reads the TOD clock of CIA1 on the C64 and C128. Since systime was a
dummy routine common for all CBMs before, this change adds an individual dummy
routine for all other CBM systems. CBM510/610 do also have a TOD clock, so a
similar function as in the C64 could be used ...
git-svn-id: svn://svn.cc65.org/cc65/trunk@3974 b7a2c559-68d2-44c3-8de9-860c34a00d81
before calling initlib because initlib calls contructors and may install
drivers, which enable hardware interrupts. Similar for donelib.
git-svn-id: svn://svn.cc65.org/cc65/trunk@3897 b7a2c559-68d2-44c3-8de9-860c34a00d81
about the driver, the mouse kernel needs to know. Current supported: Two flags
to enable interrupts before or after calling the driver INSTALL routine.
git-svn-id: svn://svn.cc65.org/cc65/trunk@3741 b7a2c559-68d2-44c3-8de9-860c34a00d81
