hi all,
I am on the learning stage of LPC2148 and I have done basic programs like interrupts ... ADC ... TIMER/COUNTER. But all the code I have written is in C Language.
Though I had written some basic progarams of LED in assembly but not the interrupt part.
Could any one here tell me what are the rules to write the assembly code for interrupts i.e. for FIQ, IRQ and NV IRQ.
If possible plz guide me with some source code.
I am using KEIL uvision 4.
Arvind Shrivastava
Comment out the below line in your Startup.s
IMPORT __use_two_region_memory
Save the below code as "ASM_Test.s"
ARM AREA ||.text||, CODE, READONLY, ALIGN=2 Timer0Handler PROC ;;;14 ;;;15 void Timer0Handler(void) __irq PUSH {r0,r1} ;;;16 { ;;;17 T0IR = 1; /* Clear Interrupt Flag */ MOV r0,#1 LDR r1,|L1.172| STR r0,[r1,#0] ;;;18 FIO3CLR = (1<<26); /* LED On */ MOV r0,#0x4000000 RSB r1,r1,r0,LSL #3 STR r0,[r1,#0x7c] ;;;19 VICVectAddr = 0; /* Acknowledge Interrupt */ MOV r0,#0 STR r0,[r0,#-0x100] ;;;20 } POP {r0,r1} SUBS pc,lr,#4 ;;;21 ENDP init_stuff PROC ;;;22 ;;;23 void init_stuff(void) ADR r0,Timer0Handler ;;;24 { ;;;25 Timer0_Vect_Addr = (unsigned long)Timer0Handler; /* Set Interrupt Vector */ MOV r1,#0 STR r0,[r1,#-0xef0] ;;;26 Timer0_Vect_Prio = HIGHEST_PRIORITY; MOV r0,#1 STR r0,[r1,#-0xdf0] ;;;27 VICIntEnable = 1 << TIMER0_INT; /* Enable Interrupt */ MOV r0,#0x10 STR r0,[r1,#-0xff0] ;;;28 ;;;29 T0MR0 = TIME_INTERVAL; LDR r0,|L1.176| LDR r1,|L1.172| STR r0,[r1,#0x18] ;;;30 T0MCR = 3; MOV r0,#3 STR r0,[r1,#0x14] ;;;31 T0TCR = 1; MOV r0,#1 STR r0,[r1,#4] ;;;32 ;;;33 FIO3DIR |= (1<<26); // 1 for Output RSB r0,r1,r0,LSL #29 LDR r0,[r0,#0x60] ORR r0,r0,#0x4000000 RSB r1,r1,r1,LSL #15 STR r0,[r1,#0x60] ;;;34 } BX lr ;;;35 ENDP EXPORT __main __main PROC ;;;36 ;;;37 int main(void) PUSH {lr} ;;;38 { ;;;39 init_stuff(); BL init_stuff ;;;40 ;;;41 while(1) B |L1.168| |L1.136| ;;;42 { ;;;43 if ( T0TC > (TIME_INTERVAL/2) ) LDR r0,|L1.172| LDR r0,[r0,#8] LDR r1,|L1.180| CMP r0,r1 BLS |L1.168| ;;;44 FIO3SET = (1<<26); /* LED Off */ MOV r0,#0x4000000 LDR r1,|L1.184| STR r0,[r1,#0x78] |L1.168| B |L1.136| ;;;45 } ;;;46 } ;;;47 ENDP |L1.172| DCD 0xe0004000 |L1.176| DCD 0x007a11ff |L1.180| DCD 0x003d08ff |L1.184| DCD 0x3fffc000 __ARM_use_no_argv EQU 0 END
Create a project with the Startup.s and ASM_Test.s. Build it, Run.
I don't have too much time for this demo project.
I haven't studied the assembly code, that KEIL toolchain generated for me, I just quickly modified them to fit my need. There were some warnings when I built this assembly demo project. And the LED blinking was not regular as what I expected, when I tested this project with my LPC2368 board. So, this assembly demo project is very low quality, but it seems work.
Now, I have quickly done my homework.
Hi John Linq,
thanx a alot dear for your kind help, guidance and efforts. I really appreciate your work!!!
thanks once again
regards Arvind