\size normal
-SDCC 2.4.5
+SDCC 2.4.7
\size footnotesize
\newline
\end_inset
- Causes the linker use unused register banks for data variables or stack.
+ Causes the linker to use unused register banks for data variables and pack
+ data, idata and stack together.
+ This is the default now.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-no-pack-iram
+\series default
+\SpecialChar ~
+
+\begin_inset LatexCommand \index{-\/-pack-iram}
+
+\end_inset
+
+ Causes the linker to use old style for allocating memory areas.
\layout Subsection
DS390 / DS400 Options
Parameters and Local Variables for more details.
If this option is used all source files in the project should be compiled
with this option.
+ It automatically implies --int-long-reent and --float-reent.
\layout List
\labelwidthstring 00.00.0000
/
\end_inset
--nostdincl
-\begin_inset LatexCommand \index{-\/-nostdincl}
+-nostdinc
+\begin_inset LatexCommand \index{-\/-nostdinc}
\end_inset
\layout Standard
-Paged xdata access is currently not as straightforward as using the other
- addressing modes of a 8051.
+Paged xdata access is just as straightforward as using the other addressing
+ modes of a 8051.
+ It is typically located at the start of xdata and has a maximum size of
+ 256 bytes.
The following example writes 0x01 to the address pointed to.
Please note, pdata access physically accesses xdata memory.
The high byte of the address is determined by port P2
movx @r0,a
\layout Standard
-Be extremely carefull if you use pdata together with the -
+If the -
\begin_inset ERT
status Collapsed
\end_inset
- option.
+ option is used the pdata memory area is followed by the xstack memory area
+ and the sum of their sizes is limited to 256 bytes.
\layout Subsubsection
code
grows, it will use up the remaining register banks, and the 16 bytes used
by the 128 bit variables, and 80 bytes for general purpose use.
- If any bit variables are used, the data variables will be placed after
- the byte holding the last bit variable.
+ If any bit variables are used, the data variables will be placed in unused
+ register banks and after the byte holding the last bit variable.
For example, if register banks 0 and 1 are used, and there are 9 bit variables
(two bytes used),
\emph on
data
\emph default
- variables will be placed starting at address 0x22.
+ variables will be placed starting from address 0x10 to 0x20 and continue
+ at address 0x22.
You can also use -
\begin_inset ERT
status Collapsed
\layout Standard
-By default the 8051 linker will place the stack after the last byte of data
+By default the 8051 linker will place the stack after the last byte of (i)data
variables.
Option -
\begin_inset ERT
or perform some other critical operation prior to static & global variable
initialization.
On some mcs51 variants xdata has to be explicitly enabled before it can
- be accessed, this is the place to do it.
- The startup code clears the complete 256 byte of idata memory, this might
- cause problems for 128 byte devices (endless loop reported for Chipcon
- CC1010).
+ be accessed or if the watchdog needs to be disabled, this is the place
+ to do it.
+ The startup code clears all internal data memory, 256 bytes by default,
+ but from 0 to n-1 if
+\emph on
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-iram-size
+\begin_inset LatexCommand \index{-\/-iram-size}
+
+\end_inset
+
+n
+\emph default
+ is used.
+ (recommended for Chipcon CC1010).
\layout Standard
See also the compiler option
\layout Standard
-
-\series bold
-Attention
-\series default
-: this option wasn't maintained for a long time and is quite buggy.
- Small programs might work.
- You've been warned!
-\layout Standard
-
The external stack (-
\begin_inset ERT
status Collapsed
\end_inset
- memory (usually at the start of the external ram segment) and is 256 bytes
- in size.
+ memory (usually at the start of the external ram segment) and uses all
+ unused space in pdata (max.
+ 256 bytes).
When -
\begin_inset ERT
status Collapsed
option, all parameters and local variables are allocated on the external
stack (note: support libraries will need to be recompiled with the same
- options).
+ options.
+ There is a predefined target in the library makefile).
\layout Standard
The compiler outputs the higher order address byte of the external ram segment
/
\end_inset
--stack-auto Auto variables that are function parameters, will be saved on
- stack by default.
-
-\emph on
-There is no need to specify this in the command line.
-\layout List
-\labelwidthstring 00.00.0000
-
--
-\begin_inset ERT
-status Collapsed
-
-\layout Standard
-
-\backslash
-/
-\end_inset
-
--float-reent All floating point functions are reentrant by default.
-
-\emph on
-There is no need to specifiy this in the command line.
-\layout List
-\labelwidthstring 00.00.0000
-
--
-\begin_inset ERT
-status Collapsed
-
-\layout Standard
-
-\backslash
-/
-\end_inset
-
-callee-saves See -
\begin_inset ERT
status Collapsed
/
\end_inset
--pgen-bank Instructs the port to insert BANKSEL directives before instructions
- that use the Bank Select Register (BSR).
+-nodefaultlibs do not link default libraries when linking.
+\layout List
+\labelwidthstring 00.00.0000
+
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-obanksel=# Set optimization level for inserting BANKSELs.
+\begin_deeper
+\layout List
+\labelwidthstring 00.00.0000
+
+0 is no optimization
+\layout List
+\labelwidthstring 00.00.0000
+
+1 checkes previous used register and if it is the same then doesn't emit
+ BANKSEL, accounts only for labels.
+\end_deeper
\layout List
\labelwidthstring 00.00.0000
/
\end_inset
--pomit-config-words Instructs the port to omit the generation of the configurati
-on words.
+-pomit-config-words Omit the generation of the configuration words.
\layout List
\labelwidthstring 00.00.0000
/
\end_inset
--pomit-ivt Instructs the port to omit the generation of the interrupt vectors
+-pomit-ivt Omit the generation of the interrupt vectors.
\layout List
\labelwidthstring 00.00.0000
/
\end_inset
--pleave-reset-vector Used in conjuction with the previous command, instructs
- the port NOT to omit the reset vector.
+-pleave-reset-vector Used in conjuction with -
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-pomit-ivt, instructs the port NOT to omit the reset vector.
\layout List
\labelwidthstring 00.00.0000
\end_inset
-link= sets the full path and name of an external linker to call.
+\layout List
+\labelwidthstring 00.00.0000
+
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-call-tree dump call tree in .calltree file
+\layout List
+\labelwidthstring 00.00.0000
+
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-mplab-comp MPLAB compatibility option.
+ Currently only suppresses special gpasm directives.
+\layout List
+\labelwidthstring 00.00.0000
+
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-use-crt= Use a custom run-time module instead of the defaults.
+\layout List
+\labelwidthstring 00.00.0000
+
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-no-crt Don't link the default run-time modules
+\layout List
+\labelwidthstring 00.00.0000
+
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-flr-support When entering/leaving a function, call support functions to
+ store/restore used registers
\layout Subsubsection
Debugging Options
\end_inset
-pcode-verbose Enable pcode debugging information in translation.
+\layout List
+\labelwidthstring 00.00.0000
+
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-denable-peeps Force the usage of peepholes.
+ Use with care.
+\layout List
+\labelwidthstring 00.00.0000
+
+-
+\begin_inset ERT
+status Collapsed
+
+\layout Standard
+
+\backslash
+/
+\end_inset
+
+-gstack Trace push/pops for stack pointer overflow
\layout Subsection
Preprocessor Macros
stack pragma stack forces the code generator to initialize the stack & frame
pointers at a specific address.
- This is an adhoc solution since gplink does not support yet stack.
- When the gplink issue is resolved the pragma will be deprecated
-\begin_inset Foot
-collapsed true
+ This is an adhoc solution for cases where no STACK directive is available
+ in the linker script or gplink is not instructed to create a stack section.
+\newline
+The stack pragma should be used only once in a project.
+ Multiple pragmas may result in indeterminate behaviour of the program.
+\newline
+The format is as follows:
+\layout LyX-Code
+#pragma stack bottom_address [stack_size]
\layout Standard
\emph on
-It is important to initialize the stack, otherwise strange things can happen.
- Stack is not initialized by default because there are some sources that
- do not require it.
- (like library sources)
-\end_inset
+bottom_address
+\emph default
+ is the lower bound of the stack section.
+ The stack pointer initially will point at address (bottom_address+stack_size-1).
+\layout LyX-Code
-.
-\newline
-The stack pragma should be used only once in a project.
- Multiple pragmas may result in indeterminate behaviour of the program.
+Example:
+\layout LyX-Code
+
+\layout LyX-Code
+
+/* initializes stack of 100 bytes at RAM address 0x200 */
+\layout LyX-Code
+
+#pragma stack 0x200 100
+\layout List
+\labelwidthstring 00.00.0000
+
+code place a function symbol at static FLASH address
\layout LyX-Code
Example:
\layout LyX-Code
-/* initializes stack at RAM address 0x5ff */
+/* place function test_func at 0x4000 */
\layout LyX-Code
-#pragma stack 0x5ff
+#pragma code test_func 0x4000
\layout List
\labelwidthstring 00.00.0000
The following stack models are supported by the PIC16 port
\layout Itemize
-small model
+
+\noun on
+small
+\noun default
+ model
\layout Itemize
-large model
+
+\noun on
+large
+\noun default
+ model
\layout Standard
\layout Standard
-\series bold
-Currently stack and frame pointers should be initialized explicit by the
- user at the desired Data RAM position (see
-\begin_inset LatexCommand \ref{sub:PIC16_Pragmas}
+\noun on
+Large
+\noun default
+stack model is currently not working properly throughout the code generator.
+ So its use is not advised.
+ Also there are some other points that need special care:
+\layout Enumerate
-\end_inset
+Do not create stack sections with size more than one physical bank (that
+ is 256 bytes)
+\layout Enumerate
+
+Stack sections should no cross physical bank limits (i.e.
+ #pragma stack 0x50 0x100)
+\layout Standard
- Pragma stack).
- Uninitialized stack and frame pointers can result in unexpected behavior
- of the resulting binary.
+These limitations are caused by the fact that only FSRxL is modified when
+ using SMALL stack model, so no more than 256 bytes of stack can be used.
+ This problem will disappear after LARGE model is fully implemented.
\layout Subsection
Function return values
projects / fw / sdcc / blobdiff