I2C interrupt in arm microcontroller

[arunraj1984]

Hello,
I am using the keil microvision 4. and the code is below.

after configure the I2CONSET the status byte is changing to 0x08 but the code does not entering the ISR.

is there any mistake in initialize the interrupts

Thankyou

#include <LPC210x.H>


void ISR(void)__irq
{

switch (I2STAT) 		// Read result code and switch to next action 
{
case ( 0x08): 			// Start bit 
I2CONCLR = 0x28;    	// Clear start bit 
I2DAT = 0x80; 	// Send address and
						// write bit  
break; 					
case (0x18): 			// Slave address+W, ACK 
I2DAT = 72;		 // Write data to tx register 
 break; 
case (0x20): 			// Slave address +W, Not ACK 
I2DAT = 80; 	// Resend address and write bit 
 break; 
case (0x28): 			// Data sent, Ack 
I2CONSET = 0x10; 		// Stop condition 
 break; 
 default :  
 break;  
 } 

I2CONCLR = 0x08;   // Clear I2C interrupt flag 
VICVectAddr = 0x00000000; // Clear interrupt in
}

void init()
{


PINSEL0 = 0X50;
I2SCLH = 0X0C;
I2SCLL = 0X0D;

I2ADR = 0x40;

VICIntEnClr = 0xffffffff;
    VICVectAddr = 0;
    VICIntSelect = 0;

VICIntEnable = 0x200;				// ENABLING i2c INTERRUPT
VICVectCntl0 = 0x29;
VICVectAddr0 = (unsigned int)ISR;
}

int main()
{

init();

I2CONSET = 0x64;

while(1)
{
IODIR = 0x0f;
IOSET = 0x0f;
IOCLR = 0x0f;

}



}

 

[ckshivaram]

which startup code are you using???

 

[yanzixuan]

have you add your I2C ISR to your startup file??

 

[arunraj1984]

Sorry for the delay.

The start up code is below.

This code file is added when a project is created.

do we need to configure this file?

;/*****************************************************************************/
;/* STARTUP.S: Startup file for Philips LPC2000                               */
;/*****************************************************************************/
;/* <<< Use Configuration Wizard in Context Menu >>>                          */ 
;/*****************************************************************************/
;/* This file is part of the uVision/ARM development tools.                   */
;/* Copyright (c) 2005-2007 Keil Software. All rights reserved.               */
;/* This software may only be used under the terms of a valid, current,       */
;/* end user licence from KEIL for a compatible version of KEIL software      */
;/* development tools. Nothing else gives you the right to use this software. */
;/*****************************************************************************/


;/*
; *  The STARTUP.S code is executed after CPU Reset. This file may be 
; *  translated with the following SET symbols. In uVision these SET 
; *  symbols are entered under Options - ASM - Define.
; *
; *  REMAP: when set the startup code initializes the register MEMMAP 
; *  which overwrites the settings of the CPU configuration pins. The 
; *  startup and interrupt vectors are remapped from:
; *     0x00000000  default setting (not remapped)
; *     0x80000000  when EXTMEM_MODE is used
; *     0x40000000  when RAM_MODE is used
; *
; *  EXTMEM_MODE: when set the device is configured for code execution
; *  from external memory starting at address 0x80000000.
; *
; *  RAM_MODE: when set the device is configured for code execution
; *  from on-chip RAM starting at address 0x40000000.
; *
; *  EXTERNAL_MODE: when set the PIN2SEL values are written that enable
; *  the external BUS at startup.
; */


; Standard definitions of Mode bits and Interrupt (I & F) flags in PSRs

Mode_USR        EQU     0x10
Mode_FIQ        EQU     0x11
Mode_IRQ        EQU     0x12
Mode_SVC        EQU     0x13
Mode_ABT        EQU     0x17
Mode_UND        EQU     0x1B
Mode_SYS        EQU     0x1F

I_Bit           EQU     0x80            ; when I bit is set, IRQ is disabled
F_Bit           EQU     0x40            ; when F bit is set, FIQ is disabled


;// <h> Stack Configuration (Stack Sizes in Bytes)
;//   <o0> Undefined Mode      <0x0-0xFFFFFFFF:8>
;//   <o1> Supervisor Mode     <0x0-0xFFFFFFFF:8>
;//   <o2> Abort Mode          <0x0-0xFFFFFFFF:8>
;//   <o3> Fast Interrupt Mode <0x0-0xFFFFFFFF:8>
;//   <o4> Interrupt Mode      <0x0-0xFFFFFFFF:8>
;//   <o5> User/System Mode    <0x0-0xFFFFFFFF:8>
;// </h>

UND_Stack_Size  EQU     0x00000000
SVC_Stack_Size  EQU     0x00000008
ABT_Stack_Size  EQU     0x00000000
FIQ_Stack_Size  EQU     0x00000000
IRQ_Stack_Size  EQU     0x00000080
USR_Stack_Size  EQU     0x00000400

ISR_Stack_Size  EQU     (UND_Stack_Size + SVC_Stack_Size + ABT_Stack_Size + \
                         FIQ_Stack_Size + IRQ_Stack_Size)

                AREA    STACK, NOINIT, READWRITE, ALIGN=3

Stack_Mem       SPACE   USR_Stack_Size
__initial_sp    SPACE   ISR_Stack_Size

Stack_Top


;// <h> Heap Configuration
;//   <o>  Heap Size (in Bytes) <0x0-0xFFFFFFFF>
;// </h>

Heap_Size       EQU     0x00000000

                AREA    HEAP, NOINIT, READWRITE, ALIGN=3
__heap_base
Heap_Mem        SPACE   Heap_Size
__heap_limit


; VPBDIV definitions
VPBDIV          EQU     0xE01FC100      ; VPBDIV Address

;// <e> VPBDIV Setup
;// <i> Peripheral Bus Clock Rate
;//   <o1.0..1>   VPBDIV: VPB Clock
;//               <0=> VPB Clock = CPU Clock / 4
;//               <1=> VPB Clock = CPU Clock
;//               <2=> VPB Clock = CPU Clock / 2
;//   <o1.4..5>   XCLKDIV: XCLK Pin
;//               <0=> XCLK Pin = CPU Clock / 4
;//               <1=> XCLK Pin = CPU Clock
;//               <2=> XCLK Pin = CPU Clock / 2
;// </e>
VPBDIV_SETUP    EQU     0
VPBDIV_Val      EQU     0x00000000


; Phase Locked Loop (PLL) definitions
PLL_BASE        EQU     0xE01FC080      ; PLL Base Address
PLLCON_OFS      EQU     0x00            ; PLL Control Offset
PLLCFG_OFS      EQU     0x04            ; PLL Configuration Offset
PLLSTAT_OFS     EQU     0x08            ; PLL Status Offset
PLLFEED_OFS     EQU     0x0C            ; PLL Feed Offset
PLLCON_PLLE     EQU     (1<<0)          ; PLL Enable
PLLCON_PLLC     EQU     (1<<1)          ; PLL Connect
PLLCFG_MSEL     EQU     (0x1F<<0)       ; PLL Multiplier
PLLCFG_PSEL     EQU     (0x03<<5)       ; PLL Divider
PLLSTAT_PLOCK   EQU     (1<<10)         ; PLL Lock Status

;// <e> PLL Setup
;//   <o1.0..4>   MSEL: PLL Multiplier Selection
;//               <1-32><#-1>
;//               <i> M Value
;//   <o1.5..6>   PSEL: PLL Divider Selection
;//               <0=> 1   <1=> 2   <2=> 4   <3=> 8
;//               <i> P Value
;// </e>
PLL_SETUP       EQU     1
PLLCFG_Val      EQU     0x00000024


; Memory Accelerator Module (MAM) definitions
MAM_BASE        EQU     0xE01FC000      ; MAM Base Address
MAMCR_OFS       EQU     0x00            ; MAM Control Offset
MAMTIM_OFS      EQU     0x04            ; MAM Timing Offset

;// <e> MAM Setup
;//   <o1.0..1>   MAM Control
;//               <0=> Disabled
;//               <1=> Partially Enabled
;//               <2=> Fully Enabled
;//               <i> Mode
;//   <o2.0..2>   MAM Timing
;//               <0=> Reserved  <1=> 1   <2=> 2   <3=> 3
;//               <4=> 4         <5=> 5   <6=> 6   <7=> 7
;//               <i> Fetch Cycles
;// </e>
MAM_SETUP       EQU     1
MAMCR_Val       EQU     0x00000002
MAMTIM_Val      EQU     0x00000004


; External Memory Controller (EMC) definitions
EMC_BASE        EQU     0xFFE00000      ; EMC Base Address
BCFG0_OFS       EQU     0x00            ; BCFG0 Offset
BCFG1_OFS       EQU     0x04            ; BCFG1 Offset
BCFG2_OFS       EQU     0x08            ; BCFG2 Offset
BCFG3_OFS       EQU     0x0C            ; BCFG3 Offset

;// <e> External Memory Controller (EMC)
EMC_SETUP       EQU     0

;//   <e> Bank Configuration 0 (BCFG0)
;//     <o1.0..3>   IDCY: Idle Cycles <0-15>
;//     <o1.5..9>   WST1: Wait States 1 <0-31>
;//     <o1.11..15> WST2: Wait States 2 <0-31>
;//     <o1.10>     RBLE: Read Byte Lane Enable
;//     <o1.26>     WP: Write Protect
;//     <o1.27>     BM: Burst ROM
;//     <o1.28..29> MW: Memory Width  <0=>  8-bit  <1=> 16-bit
;//                                   <2=> 32-bit  <3=> Reserved
;//   </e>
BCFG0_SETUP EQU         0
BCFG0_Val   EQU         0x0000FBEF

;//   <e> Bank Configuration 1 (BCFG1)
;//     <o1.0..3>   IDCY: Idle Cycles <0-15>
;//     <o1.5..9>   WST1: Wait States 1 <0-31>
;//     <o1.11..15> WST2: Wait States 2 <0-31>
;//     <o1.10>     RBLE: Read Byte Lane Enable
;//     <o1.26>     WP: Write Protect
;//     <o1.27>     BM: Burst ROM
;//     <o1.28..29> MW: Memory Width  <0=>  8-bit  <1=> 16-bit
;//                                   <2=> 32-bit  <3=> Reserved
;//   </e>
BCFG1_SETUP EQU         0
BCFG1_Val   EQU         0x0000FBEF

;//   <e> Bank Configuration 2 (BCFG2)
;//     <o1.0..3>   IDCY: Idle Cycles <0-15>
;//     <o1.5..9>   WST1: Wait States 1 <0-31>
;//     <o1.11..15> WST2: Wait States 2 <0-31>
;//     <o1.10>     RBLE: Read Byte Lane Enable
;//     <o1.26>     WP: Write Protect
;//     <o1.27>     BM: Burst ROM
;//     <o1.28..29> MW: Memory Width  <0=>  8-bit  <1=> 16-bit
;//                                   <2=> 32-bit  <3=> Reserved
;//   </e>
BCFG2_SETUP EQU         0
BCFG2_Val   EQU         0x0000FBEF

;//   <e> Bank Configuration 3 (BCFG3)
;//     <o1.0..3>   IDCY: Idle Cycles <0-15>
;//     <o1.5..9>   WST1: Wait States 1 <0-31>
;//     <o1.11..15> WST2: Wait States 2 <0-31>
;//     <o1.10>     RBLE: Read Byte Lane Enable
;//     <o1.26>     WP: Write Protect
;//     <o1.27>     BM: Burst ROM
;//     <o1.28..29> MW: Memory Width  <0=>  8-bit  <1=> 16-bit
;//                                   <2=> 32-bit  <3=> Reserved
;//   </e>
BCFG3_SETUP EQU         0
BCFG3_Val   EQU         0x0000FBEF

;// </e> End of EMC


; External Memory Pins definitions
PINSEL2         EQU     0xE002C014      ; PINSEL2 Address
PINSEL2_Val     EQU     0x0E6149E4      ; CS0..3, OE, WE, BLS0..3, 
                                        ; D0..31, A2..23, JTAG Pins


                PRESERVE8
                

; Area Definition and Entry Point
;  Startup Code must be linked first at Address at which it expects to run.

                AREA    RESET, CODE, READONLY
                ARM


; 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, [PC, #-0x0FF0]     ; Vector from VicVectAddr
                LDR     PC, FIQ_Addr

Reset_Addr      DCD     Reset_Handler
Undef_Addr      DCD     Undef_Handler
SWI_Addr        DCD     SWI_Handler
PAbt_Addr       DCD     PAbt_Handler
DAbt_Addr       DCD     DAbt_Handler
                DCD     0                      ; Reserved Address 
IRQ_Addr        DCD     IRQ_Handler
FIQ_Addr        DCD     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       IRQ_Handler
FIQ_Handler     B       FIQ_Handler


; Reset Handler

                EXPORT  Reset_Handler
Reset_Handler   


; Setup External Memory Pins
                IF      :DEF:EXTERNAL_MODE
                LDR     R0, =PINSEL2
                LDR     R1, =PINSEL2_Val
                STR     R1, [R0]
                ENDIF


; Setup External Memory Controller
                IF      EMC_SETUP <> 0
                LDR     R0, =EMC_BASE

                IF      BCFG0_SETUP <> 0
                LDR     R1, =BCFG0_Val
                STR     R1, [R0, #BCFG0_OFS]
                ENDIF

                IF      BCFG1_SETUP <> 0
                LDR     R1, =BCFG1_Val
                STR     R1, [R0, #BCFG1_OFS]
                ENDIF

                IF      BCFG2_SETUP <> 0
                LDR     R1, =BCFG2_Val
                STR     R1, [R0, #BCFG2_OFS]
                ENDIF

                IF      BCFG3_SETUP <> 0
                LDR     R1, =BCFG3_Val
                STR     R1, [R0, #BCFG3_OFS]
                ENDIF

                ENDIF   ; EMC_SETUP


; Setup VPBDIV
                IF      VPBDIV_SETUP <> 0
                LDR     R0, =VPBDIV
                LDR     R1, =VPBDIV_Val
                STR     R1, [R0]
                ENDIF


; Setup PLL
                IF      PLL_SETUP <> 0
                LDR     R0, =PLL_BASE
                MOV     R1, #0xAA
                MOV     R2, #0x55

;  Configure and Enable PLL
                MOV     R3, #PLLCFG_Val
                STR     R3, [R0, #PLLCFG_OFS] 
                MOV     R3, #PLLCON_PLLE
                STR     R3, [R0, #PLLCON_OFS]
                STR     R1, [R0, #PLLFEED_OFS]
                STR     R2, [R0, #PLLFEED_OFS]

;  Wait until PLL Locked
PLL_Loop        LDR     R3, [R0, #PLLSTAT_OFS]
                ANDS    R3, R3, #PLLSTAT_PLOCK
                BEQ     PLL_Loop

;  Switch to PLL Clock
                MOV     R3, #(PLLCON_PLLE:OR:PLLCON_PLLC)
                STR     R3, [R0, #PLLCON_OFS]
                STR     R1, [R0, #PLLFEED_OFS]
                STR     R2, [R0, #PLLFEED_OFS]
                ENDIF   ; PLL_SETUP


; Setup MAM
                IF      MAM_SETUP <> 0
                LDR     R0, =MAM_BASE
                MOV     R1, #MAMTIM_Val
                STR     R1, [R0, #MAMTIM_OFS] 
                MOV     R1, #MAMCR_Val
                STR     R1, [R0, #MAMCR_OFS] 
                ENDIF   ; MAM_SETUP


; Memory Mapping (when Interrupt Vectors are in RAM)
MEMMAP          EQU     0xE01FC040      ; Memory Mapping Control
                IF      :DEF:REMAP
                LDR     R0, =MEMMAP
                IF      :DEF:EXTMEM_MODE
                MOV     R1, #3
                ELIF    :DEF:RAM_MODE
                MOV     R1, #2
                ELSE
                MOV     R1, #1
                ENDIF
                STR     R1, [R0]
                ENDIF


; Initialise Interrupt System
;  ...


; Setup Stack for each mode

                LDR     R0, =Stack_Top

;  Enter Undefined Instruction Mode and set its Stack Pointer
                MSR     CPSR_c, #Mode_UND:OR:I_Bit:OR:F_Bit
                MOV     SP, R0
                SUB     R0, R0, #UND_Stack_Size

;  Enter Abort Mode and set its Stack Pointer
                MSR     CPSR_c, #Mode_ABT:OR:I_Bit:OR:F_Bit
                MOV     SP, R0
                SUB     R0, R0, #ABT_Stack_Size

;  Enter FIQ Mode and set its Stack Pointer
                MSR     CPSR_c, #Mode_FIQ:OR:I_Bit:OR:F_Bit
                MOV     SP, R0
                SUB     R0, R0, #FIQ_Stack_Size

;  Enter IRQ Mode and set its Stack Pointer
                MSR     CPSR_c, #Mode_IRQ:OR:I_Bit:OR:F_Bit
                MOV     SP, R0
                SUB     R0, R0, #IRQ_Stack_Size

;  Enter Supervisor Mode and set its Stack Pointer
                MSR     CPSR_c, #Mode_SVC:OR:I_Bit:OR:F_Bit
                MOV     SP, R0
                SUB     R0, R0, #SVC_Stack_Size

;  Enter User Mode and set its Stack Pointer
                MSR     CPSR_c, #Mode_USR
                IF      :DEF:__MICROLIB

                EXPORT __initial_sp

                ELSE

                MOV     SP, R0
                SUB     SL, SP, #USR_Stack_Size

                ENDIF


; Enter the C code

                IMPORT  __main
                LDR     R0, =__main
                BX      R0


                IF      :DEF:__MICROLIB

                EXPORT  __heap_base
                EXPORT  __heap_limit

                ELSE
; User Initial Stack & Heap
                AREA    |.text|, CODE, READONLY

                IMPORT  __use_two_region_memory
                EXPORT  __user_initial_stackheap
__user_initial_stackheap

                LDR     R0, =  Heap_Mem
                LDR     R1, =(Stack_Mem + USR_Stack_Size)
                LDR     R2, = (Heap_Mem +      Heap_Size)
                LDR     R3, = Stack_Mem
                BX      LR
                ENDIF


                END