startup_lpc17xx.s GNU

Stefano wrote:
> I have installed Sourcery G++ Lite compiler in Keil IDE.
> Now I start to try to compile a simple Keil example (IOTest) for LPC1768
> Cortex M3.
> The assembler language is different and I need to replace the file
> startup_lpc17xx.s, where can I find the correct version for Sourcery
> assembler ?

NXP provides a "CMSIS-Complient Driver Library" on it's web-site. 
Filename is lpc17xx.cmsis.driver.library.zip. There is startup-code for 
gcc in this package (search .../gcc/startup_LPC17xx.s).
If have not worked with LPC17xx so far but please note that the 
startup-code in the Keil/ARM-examples often includes additional 
instructions in the assembler-setup (e.g. for PLL, clocks). But there is 
initialistaion-code for these settings available in system_LPC17xx.c in 
NXP's archive so porting should be easy.

It seems that the used linker-script is incompatible with the 
startup-code. The undefined symbols get defined by the linker since 
there are instructions for this in the linker-script. The symbols are 
basically variables which hold memory-addresses (for example top of 
stack) and are later used during assembly of the startup-code.
Did you use one of the linker-scripts which come with NXP's package 
(*_gnu.ld)?

Sorry. I do not have a simple ready-made linker-scripts which are 
compatible with the LPC17xx startup-code from NXP. I do not own a board 
with such a controller so I had no reason to create anything for it. But 
if the scripts and startup from NXP work just use them for now. You can 
read more about linker-scripts an the instructions in it in the binutils 
ld manual. The scripts from NXP seem to be based on the Codesourcery 
"standard" for linker-scripts and startup. IRC there is some information 
on this in the "getting-started" PDF-file included in CS G++ lite.

Maybe this is useful for you: 
http://www.siwawi.arubi.uni-kl.de/avr_projects/arm_projects/arm_memcards/index.html#chanfat_stm32
It's for another controller also with Cortex-M3 core and it should be 
rather easy to port the linker-script and startup-code to LPC17xx. 
Decide yourself if it's "simple" enough

Maybe someone else can jump in here and provide "simple" an tested 
examples for LPC17xx.

Stefano wrote:
> OK, now I am near able to work.
> I have an other question about CodeSourcery in Keil:

The forum/support-request-form at keil.com might be a better place to 
ask questions on µVision.

> - The "download code to flash memory" is no longer enabled, then I
> cannot program the target, is possible enable this function ?

Did you verify that Options for Target/Utilities is configured correctly 
for the used interface? Is an elf-file generated? Did you try with 
"generate hex-file" enabled in the project settings. The download 
function worked for me even when using the GNU cross-toolchain at least 
with older versions of the evaluation-software. I have not played with 
the latest version.

> - The debugger function remain limited to 32K ?

As far as I know: yes. The limiation of the debugger and simulator is 
not related to the used cross-compiler.

> or is possible to debug code long more then 32k ?

Keil/ARM sells unlimited versions and IRC also a less expensive package 
with 256kBytes limitation.