Posted on May 17, 2011 at 09:41Hi,
Maybe your problem will be the cause of nested interrupt.
also, I had same problem. would you modify the IRQ handler as following in the vect.s
IRQHandler
SUB lr,lr,#4 ;// Update the link register
SaveContext r0,r12 ;// Save the workspace plus the current
;// return address lr_irq and spsr_irq
LDR r0, = VectorAddress
LDR r0, [r0] ;// Read the routine address
;//LDR r1, = VectorAddressDaisy
;//LDR r1, [r1]
;// Padding between the acknowledge and re-enable of interrupts
;// For more details, please refer to the following URL
;//
http://www.arm.com/support/faqip/3682.html
;//NOP
;//NOP
;//MSR cpsr_c,#0x1F | I_Bit ;// Switch to SYS mode and disable IRQ modified by KMSHIM, 2007/03/15
;//MSR cpsr_c,#0x1F ;// Switch to SYS mode and enable IRQ
STMFD sp!,{lr} ;// Save the link register.
LDR lr, = IRQ_ReturnAddress ;// Read the return address.
BX r0 ;// Branch to the IRQ handler.
IRQ_ReturnAddress
LDMFD sp!,{lr} ;// Restore the link register.
;//MSR cpsr_c,#0xD2 | I_Bit ;// Switch to IRQ mode and disable IRQ
LDR r0, = VectorAddress ;// Write to the VectorAddress to clear the
STR r0,[r0] ;// respective interrupt in the internal interrupt
LDR r1, = VectorAddressDaisy ;// Write to the VectorAddressDaisy to clear the
STR r1,[r1] ;// respective interrupt in the internal interrupt
RestoreContext r0,r12 ;// Restore the context and return to the...
;// ...program execution.
good luck!!
best regards,
KMSHIM
