Apple-2-SW/prog8
1
0
Fork 0
mirror of https://github.com/irmen/prog8.git synced 2025-07-23 13:24:32 +00:00
Code Issues Projects Releases Wiki Activity

Kernal spelling

Browse Source
This commit is contained in:
Irmen de Jong
2022-10-29 14:10:11 +02:00
parent 0e297731a3
commit db8912a735
7 changed files with 26 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
docs/source/syntaxreference.rst
View File

@@ -57,19 +57,19 @@ Directives
Global setting, select ZeroPage handling style. Defaults to ``kernalsafe``.
- style ``kernalsafe`` -- use the part of the ZP that is 'free' or only used by BASIC routines,
and don't change anything else. This allows full use of KERNAL ROM routines (but not BASIC routines),
and don't change anything else. This allows full use of Kernal ROM routines (but not BASIC routines),
including default IRQs during normal system operation.
It's not possible to return cleanly to BASIC when the program exits. The only choice is
to perform a system reset. (A ``system_reset`` subroutine is available in the syslib to help you do this)
- style ``floatsafe`` -- like the previous one but also reserves the addresses that
are required to perform floating point operations (from the BASIC kernal). No clean exit is possible.
are required to perform floating point operations (from the BASIC Kernal). No clean exit is possible.
- style ``basicsafe`` -- the most restricted mode; only use the handful 'free' addresses in the ZP, and don't
touch change anything else. This allows full use of BASIC and KERNAL ROM routines including default IRQs
touch change anything else. This allows full use of BASIC and Kernal ROM routines including default IRQs
during normal system operation.
When the program exits, it simply returns to the BASIC ready prompt.
- style ``full`` -- claim the whole ZP for variables for the program, overwriting everything,
except the few addresses mentioned above that are used by the system's IRQ routine.
Even though the default IRQ routine is still active, it is impossible to use most BASIC and KERNAL ROM routines.
Even though the default IRQ routine is still active, it is impossible to use most BASIC and Kernal ROM routines.
This includes many floating point operations and several utility routines that do I/O, such as ``print``.
This option makes programs smaller and faster because even more variables can
be stored in the ZP (which allows for more efficient assembly code).
@@ -119,7 +119,7 @@ Directives
Sets special compiler options.
- ``enable_floats`` (module level) tells the compiler
to deal with floating point numbers (by using various subroutines from the Commodore 64 kernal).
to deal with floating point numbers (by using various subroutines from the Commodore 64 Kernal).
Otherwise, floating point support is not enabled. Normally you don't have to use this yourself as
importing the ``floats`` library is required anyway and that will enable it for you automatically.
- ``no_sysinit`` (module level) which cause the resulting program to *not* include
@@ -580,7 +580,7 @@ Multiple return values
^^^^^^^^^^^^^^^^^^^^^^
Normal subroutines can only return zero or one return values.
However, the special ``asmsub`` routines (implemented in assembly code) or ``romsub`` routines
(referencing a routine in kernal ROM) can return more than one return value.
(referencing a routine in Kernal ROM) can return more than one return value.
For example a status in the carry bit and a number in A, or a 16-bit value in A/Y registers.
It is not possible to process the results of a call to these kind of routines
directly from the language, because only single value assignments are possible.