Lpc2000

Hello Robert,

i meanwhile have my environment with gcc 3.4 for the LPC2106 running.

I used your initialization file, but got very big HEX files (arund 23 KB for
a simple example "led.c").
When you leave out the line

bl              exit            /* Should not return */

then you get a HEX file of around 1,5 KB, because "exit" includes a lot of
library functions (like malloc, ...)
I don't think it is really needed, because the endless loop is already doing
it fine ?

Greetings,

          Martin

----- Original Message ----- 
From: "Robert Adsett" <subscriptions@...>
To: <lpc2100@yahoogroups.com>
Sent: Tuesday, December 16, 2003 11:27 PM
Subject: Re: [lpc2100] Many thanks to ariusdsp -> how to build application ?


> At 05:13 PM 12/16/03 -0500, you wrote:
> >At 11:05 PM 12/16/03 +0100, you wrote:
> > >Has someone in the group already created such a linker script for the
> > >LPC2106 ?
> > >I started to modify the example, but it seems to be a non trivial task,
> > >without knowing the right syntax of a linker script.
> > >
> > >I think, what i am searching for is a "hello world" for LPC2106 with
gnu arm
> > >toolchain from source to hex-file...
> > >Leon: This is perhaps worth uploading to your website ?
> > >
> > >Greetings,
> >One linker script coming up.
>
> Oh and the startup that goes with it.
>
> /* Sample initialization file */
>
>          .extern main
>          .extern exit
>
>   /* .text is used instead of .section .text so it works with
> arm-aout too. */
>
>          .text
>          .code 32
>
>
>          .align  0
>
>          .extern __bss_beg__
>          .extern __bss_end__
>          .extern __stack_end__
>          .extern __data_beg__
>          .extern __data_end__
>          .extern __data+beg_src__
>
>          .global start
> /*      .global _mainCRTStartup */
> /*      .global _start */
>          .global endless_loop
>
> start:
> _start:
> _mainCRTStartup:
> /* Start by setting up a stack */
>          /*  Set up the stack pointer to end of bss */
>          ldr             r3, .LC6
>          mov     sp, r3
>
>          sub             sl, sp, #512    /* Still assumes 512 bytes below
sl */
>
>          mov     a2, #0          /* Second arg: fill value */
>          mov             fp, a2          /* Null frame pointer */
>          mov             r7, a2          /* Null frame pointer for Thumb
*/
>
> /*      ldr             r1, #__bss_beg__*/      /* First arg: start of
> memory block */
>
>          ldr     r1, .LC1                        /* First arg: start of
> memory block */
> /*      ldr     r3, #__bss_end__*/      /* Second arg: end of memory block
*/
>          ldr     r3, .LC2                        /* Second arg: end of
> memory block */
>          subs    r3, r3, r1                      /* Third arg: length of
> block */
>          beq             .end_clear_loop
>          mov     r2, #0
>
> .clear_loop:
>          strb    r2, [r1], #1
>          subs    r3, r3, #1
>          bgt             .clear_loop
>
> .end_clear_loop:
>
>          ldr             r1, .LC3                /* First arg: start of
> memory block */
>          ldr     r2, .LC4                /* Second arg: end of memory
block */

>          ldr     r3, .LC5
>          subs    r3, r3, r1              /* Third arg: length of block */
>          beq             .end_set_loop
>
> .set_loop:
>          ldrb    r4, [r2], #1
>          strb    r4, [r1], #1
>          subs    r3, r3, #1
>          bgt     .set_loop
>
> .end_set_loop:
>
>
>          mov             r0, #0          /*  no arguments  */
>          mov             r1, #0          /* no argv either */
>
>          bl              main
>
> endless_loop:
>          b               endless_loop
>
>          bl              exit            /* Should not return */
>
>          /* For Thumb, constants must be after the code since only
>          positive offsets are supported for PC relative addresses. */
>
>          .align 0
> .LC1:
> .word   __bss_beg__
> .LC2:
> .word   __bss_end__
> .LC3:
> .word   __data_beg__
> .LC4:
> .word   __data_beg_src__
> .LC5:
> .word   __data_end__
> .LC6:
> .word   __stack_end__
>
> .section .startup,"ax"
>          .code 32
>          .align 0
>
>          b       start
>          b       undefined_instruction_exception
>          b       software_interrupt_exception
>          b       prefetch_abort_exception
>          b       data_abort_exception
>          b       reserved_exception
>          b       interrupt_exception
>          b       fast_interrupt_exception
>
> Robert
>
>
> " 'Freedom' has no meaning of itself.  There are always restrictions,
> be they legal, genetic, or physical.  If you don't believe me, try to
> chew a radio signal. "
>
>                          Kelvin Throop, III
>
>
> To unsubscribe from this group, send an email to:
> lpc2100-unsubscribe@yahoogroups.com
>
>
>
>
> Yahoo! Groups Links
>
> To visit your group on the web, go to:
>  http://groups.yahoo.com/group/lpc2100/
>
> To unsubscribe from this group, send an email to:
>  lpc2100-unsubscribe@yahoogroups.com
>
> Your use of Yahoo! Groups is subject to:
>  http://docs.yahoo.com/info/terms/
>
>

At 11:32 PM 12/23/03 +0100, you wrote:
>Hello Robert,
>
>i meanwhile have my environment with gcc 3.4 for the LPC2106 running.
>
>I used your initialization file, but got very big HEX files (arund 23 KB for
>a simple example "led.c").
>When you leave out the line
>
>bl              exit            /* Should not return */
>
>then you get a HEX file of around 1,5 KB, because "exit" includes a lot of
>library functions (like malloc, ...)
>I don't think it is really needed, because the endless loop is already doing
>it fine ?
>
>Greetings,
>
>           Martin

Thanks Martin, looking at that I'm not sure why I left that call to exit in 
there.  You're right there is no way to get to it, might as well just get 
rid of it.

Robert





" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III