Cypress DCT-1D Podręcznik Użytkownika Pobierz pdf (Strona 22)

CHAPTER 1. THE SYST EM

Listing 1.5: Program showing contents of a special purpose register.

# i n c l u d e < s y s / t y p e s . h>

# i n c l u d e < s y s / s t a t . h>

# i n c l u d e <asm / i o . h>

# i n c l u d e <asm / s p r _ d e f s . h>

# i n c l u d e <asm / b o a r d . h>

i n t main ( i n t a rg c , char ∗a r g v [ ] )

{

unsigned lo n g v al , a d d r ;

i f ( a r g c == 2) {

a d d r = s t r t o u l ( ar g v [ 1 ] , 0 , 0 ) ;

/ ∗ Read SPR ∗/

asm ( "l.mfspr␣%0 ,%1,0" : "=r" ( v a l ) : "r" ( a d d r ) ) ;

p r i n t f ( "\nSPR␣%04lx:␣%08lx\n" , ad d r , v a l ) ;

} e l s e re t u r n −1;

re t u r n 0 ;

}

Listing 1.6: Makeﬁle to compile the program s howing an SPR (Listing 1.5).

CC = or32−u c l i b c −g c c

STRIP = or3 2−u c l i b c −s t r i p

PRGS = m f s pr

a l l : $ (PRGS)

mfs p r : mf s p r . o

$ (CC) −r −d m f s pr . o −o $@

$ ( STRIP ) −g $@

Finally the program can be downloaded with tftp. Change directory (cd) to a

writable portion of the ﬁlesystem, like for instance /var/tmp. Then start the tftp

client

> tftp IP_address_of_your_tftp_server

Retrieve the program:

> get mfspr

See section 4.3.2 for more information on how to start the TFTP server.

1 2 ... 17 18 19 20 21 22 23 24 25 26 27 ... 81 82

Brak uwag

Cypress DCT-1D Podręcznik Użytkownika Strona 22