|
And if you want to use the PtoX() utilities that I
previously emailed to this list, you'll also want the
strcpy_iPtoX().
This function is an INDIRECT string copy for ARRAYS
of STRINGS in P-memory, where both the pointer and the string data are both
stored in P-memory.
void test( void )
{
char
str[30];
strcpy_iPtoX( str,
&ErrorMessages[2] );
...
}
Regards,
William C.
Yochum
Microwave Data Systems Inc.
Principal Eng./Software 175 Science
Parkway
Phone:
(585) 242-8319
Rochester, NY 14620
FAX: (585) 241-5590
USA
You
also need to declare the data as constants
const char * const
ErrorMessages[] = {"Error string 1", "Error string 2",
..., "Error string
N"}
----- Original Message -----
From: "ra"
<r...@gmx.net>
To: <m...@yahoogroups.com>
Sent: Wednesday,
September 22, 2004 2:49 AM
Subject: [motoroladsp] strings in p-ROM for
56F8300/E> Hello again
>
> The previously posted advice works
fine for non-string data, and by
> defining a separate linker section
one can place constants in P-ROM:
>
> in the C source file,
define the section and open it:
>
>> #pragma define_section
mysection ".mysection.text" RX
>>
>> #pragma section
mysection begin
>
>> const int SomeIntegers[] = {0,1,5,3}
>
>> #pragma section mysection end
>
> And in
the linker command file add that section to the p-code:
>
>>
* (.mysection.text)> But when I try this with strings, only their pointers go
into p-rom,
> and the string space itself still gets placed in the
data.char section
> in data flash.
>
> I.e., putting
this between the "mysection" pragmas,
>> const char * ErrorMessages
[] =
>> {
>> "Welcome to Wind
Genie DSP",
>> "TRBLE
MODE ERR",
>> "DATA
ERROR",
>> "DATA
CORRUPTED",
>>
"DISPLAY ERROR",
>>
"MEMORY ERROR",
>>
"INVALID PARAMETER"
>> };
>
>
only a seven-word array "ErrorMessages" with pointers to the strings
>
goes into p-rom, whereas the data.char still goes into data-rom.
>
> Is there any trick to move the strings into p-rom, too?
>
> This is for a 56F8346 processor, which doesn't use the "rodata"
> described in app note AN1952.
>
> Many thanks in advance
for advice!
> Robert Imhoff>
>
>
_____________________________________
> Note: If you do a simple "reply"
with your email client, only the author
> of this message will receive
your answer. You need to do a "reply all" if
> you want your
answer to be distributed to the entire group.
>
>
_____________________________________
> About this discussion group:
>
> To Join: m...@yahoogroups.com
>
> To
Post: m...@yahoogroups.com
>
> To Leave:
m...@yahoogroups.com
>
> Archives:
http://www.yahoogroups.com/group/motoroladsp
>
> More Groups:
http://www.dsprelated.com/groups.php3
>
> Yahoo! Groups Links
_____________________________________
Note: If
you do a simple "reply" with your email client, only the author of this message
will receive your answer. You need to do a "reply all" if you want your
answer to be distributed to the entire group.
_____________________________________
About this discussion group:
To Join: m...@yahoogroups.com
To Post:
m...@yahoogroups.com
To Leave: m...@yahoogroups.com
Archives: http://www.yahoogroups.com/group/motoroladsp
More Groups:
http://www.dsprelated.com/groups.php3
|
// src = pointer to source char in P memory
// dst = pointer to destination char in X memory
asm void PtoX(char* dst, char* src)
{
//dst is in r2
//src is in r3
move P:(r3)+,r3
move r3,X:(r2)+
rts
}
// src = pointer to source string in P memory
// dst = pointer to destination string in X memory
void strcpyPtoX(char* dst, char* src)
{
do {
PtoX( (void *)dst, (void *)src);
src++;
} while (*dst++ != '\0');
}
// src = pointer to pointer to source string in P memory
// dst = pointer to destination string in X memory
//
// This function is useful for referencing ARRAYS of strings
// stored in Program Memory. It first copies obtains the pointer
// to the desired string, then copies the string itself.
//
void strcpy_iPtoX(char* dst, char** src)
{
char * tmp_ptr;
PtoX( (void *)&tmp_ptr, (void *)src );
strcpyPtoX( dst, tmp_ptr );
}
|