hi all,
can any body plz tell me how to handle more than one interrupts
simultaneously
in GCC .
single interrupts are working separately when I changed in startup.s
file like below:
************************************************************************ 
*******
# Exception Vectors
#  Mapped to Address 0.
#  Absolute addressing mode must be used.
#  Dummy Handlers are implemented as infinite loops which can be
modified.

Vectors:        LDR     PC, Reset_Addr
                LDR     PC, Undef_Addr
                LDR     PC, SWI_Addr
                LDR     PC, PAbt_Addr
                LDR     PC, DAbt_Addr
                NOP                            /* Reserved Vector */

    LDR     PC, IRQ_Addr
                LDR     PC, FIQ_Addr

Reset_Addr:     .word   Reset_Handler
Undef_Addr:     .word   Undef_Handler
SWI_Addr:       .word   SWI_Handler
PAbt_Addr:      .word   PAbt_Handler
DAbt_Addr:      .word   DAbt_Handler
                .word   0                      /* Reserved Address */

IRQ_Addr:       .word   uart0 /* uart0 is the service routine function
which I placed here  */
FIQ_Addr:  .word   FIQ_Handler

Undef_Handler:  B       Undef_Handler
SWI_Handler:    B       SWI_Handler
PAbt_Handler:   B       PAbt_Handler
DAbt_Handler:   B       DAbt_Handler

IRQ_Handler:    B      uart0  /* uart0 is the service routine function
which I placed here  */

FIQ_Handler:    B   FIQ_Handler
************************************************************************ 
*******
prototype defined is :
void uart0(void) _attribute_ ((interrupt ("IRQ")));
I hav alredy posted a mail earlier but not received any response yet.

now plz tell me how to handle multiple interrupts?
thanks.

Please check the documents available from Philips (Manual, Section VIC)
and ARM (ARM7TDMI referece-manual, VIC "macrocell"). Either use an
instruction like ldr pc,[pc,#-0xFF0] at the "IRQ-position" of the
exception vectors or branch to a assembler-wrapper which may use the
VIC's vector-adress as branch address to an ISR. Various source-examples
available from the yahoo-group and in the WinARM examples-collection
should demonstrate the different approaches.

Martin Thomas