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　//***************************************************************************** // LPC23xx Microcontroller Startup code for use with LPCXpresso IDE // // Version : 141204 //***************************************************************************** // // Copyright(C) NXP Semiconductors, 2013-2014 // All rights reserved. // // Software that is described herein is for illustrative purposes only // which provides customers with programming information regarding the // LPC products. This software is supplied "AS IS" without any warranties of // any kind, and NXP Semiconductors and its licensor disclaim any and // all warranties, express or implied, including all implied warranties of // merchantability, fitness for a particular purpose and non-infringement of // intellectual property rights. NXP Semiconductors assumes no responsibility // or liability for the use of the software, conveys no license or rights under any // patent, copyright, mask work right, or any other intellectual property rights in // or to any products. NXP Semiconductors reserves the right to make changes // in the software without notification. NXP Semiconductors also makes no // representation or warranty that such application will be suitable for the // specified use without further testing or modification. // // Permission to use, copy, modify, and distribute this software and its // documentation is hereby granted, under NXP Semiconductors' and its // licensor's relevant copyrights in the software, without fee, provided that it // is used in conjunction with NXP Semiconductors microcontrollers. This // copyright, permission, and disclaimer notice must appear in all copies of // this code. //***************************************************************************** #if defined (__cplusplus) #ifdef __REDLIB__ #error Redlib does not support C++ #else //***************************************************************************** // // The entry point for the C++ library startup // //***************************************************************************** extern "C" { extern void __libc_init_array(void); } #endif #endif #define WEAK __attribute__ ((weak)) #define ALIAS(f) __attribute__ ((weak, alias (#f))) //***************************************************************************** #if defined (__cplusplus) extern "C" { #endif //***************************************************************************** #if defined (__USE_CMSIS) || defined (__USE_LPCOPEN) // Declaration of external SystemInit function extern void SystemInit(void); #endif //***************************************************************************** // // Forward declaration of the default handlers. These are aliased. // When the application defines a handler (with the same name), this will // automatically take precedence over these weak definitions // //***************************************************************************** void Reset_Handler(void); WEAK void IntDefaultHandler(void); //***************************************************************************** // // Forward declaration of the specific IRQ handlers. These are aliased // to the IntDefaultHandler, which is a 'forever' loop. When the application // defines a handler (with the same name), this will automatically take // precedence over these weak definitions // //***************************************************************************** void Undef_Handler(void) ALIAS(IntDefaultHandler); void SWI_Handler(void) ALIAS(IntDefaultHandler); void PAbt_Handler(void) ALIAS(IntDefaultHandler); void DAbt_Handler(void) ALIAS(IntDefaultHandler); void IRQ_Handler(void) ALIAS(IntDefaultHandler); void FIQ_Handler(void) ALIAS(IntDefaultHandler); //***************************************************************************** // // The entry point for the application. // __main() is the entry point for Redlib based applications // main() is the entry point for Newlib based applications // //***************************************************************************** #if defined (__REDLIB__) extern void __main(void); #else extern int main(void); #endif //***************************************************************************** // // Standard definitions of Mode bits and Interrupt (I & F) flags in PSRs // //***************************************************************************** __asm(".set Mode_USR, 0x10\n"); /*; User Mode */ __asm(".set Mode_FIQ, 0x11\n"); /*; FIQ Mode */ __asm(".set Mode_IRQ, 0x12\n"); /*; IRQ Mode */ __asm(".set Mode_SVC, 0x13\n"); /*; Supervisor Mode */ __asm(".set Mode_ABT, 0x17\n"); /*; Abort Mode */ __asm(".set Mode_UNDEF, 0x1B\n"); /*; Undefined Mode */ __asm(".set Mode_SYS, 0x1F\n"); /*; System Mode */ __asm(".set I_Bit, 0x80\n"); /*; when I bit is set, IRQ is disabled */ __asm(".set F_Bit, 0x40\n"); /*; when F bit is set, FIQ is disabled */ //***************************************************************************** // // External declaration for the pointer to the stack top from the Linker Script // //***************************************************************************** extern unsigned _vStackTop; //***************************************************************************** // // Stack Sizes. The default values // //***************************************************************************** __asm(".set __SVC_Stack_Size, 0x100\n"); __asm(".set __IRQ_Stack_Size, 0x400\n"); __asm(".set __USR_Stack_Size, 0x400\n"); __asm(".set __FIQ_Stack_Size, 0x100\n"); __asm(".set __ABT_Stack_Size, 0x100\n"); __asm(".set __UND_Stack_Size, 0x100\n"); __asm(".set _ABT_Stack, (_vStackTop)\n"); __asm(".set _UND_Stack, (_ABT_Stack - __ABT_Stack_Size)\n"); __asm(".set _SVC_Stack, (_UND_Stack - __UND_Stack_Size)\n"); __asm(".set _FIQ_Stack, (_SVC_Stack - __SVC_Stack_Size)\n"); __asm(".set _IRQ_Stack, (_FIQ_Stack - __FIQ_Stack_Size)\n"); __asm(".set _USR_Stack, (_IRQ_Stack - __IRQ_Stack_Size)\n"); //***************************************************************************** #if defined (__cplusplus) } // extern "C" #endif //***************************************************************************** // // The vector table. // This relies on the linker script to place at correct location in memory. // //***************************************************************************** extern void ResetISR(void) __attribute__ ((naked, section(".isr_vector"))); void ResetISR(void) { __asm(" ldr PC, =Reset_Handler\n"); __asm(" ldr PC, =Undef_Handler\n"); __asm(" ldr PC, =SWI_Handler\n"); __asm(" ldr PC, =PAbt_Handler\n"); __asm(" ldr PC, =DAbt_Handler\n"); __asm(" nop\n"); __asm(" ldr PC, =IRQ_Handler\n"); __asm(" ldr PC, =FIQ_Handler\n"); } //***************************************************************************** // Functions to carry out the initialization of RW and BSS data sections. These // are written as separate functions rather than being inlined within the // Reset_Handler() function in order to cope with MCUs with multiple banks of // memory. //***************************************************************************** __attribute__ ((section(".after_vectors"))) void data_init(unsigned int romstart, unsigned int start, unsigned int len) { unsigned int *pulDest = (unsigned int*) start; unsigned int *pulSrc = (unsigned int*) romstart; unsigned int loop; for (loop = 0; loop < len; loop = loop + 4) *pulDest++ = *pulSrc++; } __attribute__ ((section(".after_vectors"))) void bss_init(unsigned int start, unsigned int len) { unsigned int *pulDest = (unsigned int*) start; unsigned int loop; for (loop = 0; loop < len; loop = loop + 4) *pulDest++ = 0; } #ifndef USE_OLD_STYLE_DATA_BSS_INIT //***************************************************************************** // The following symbols are constructs generated by the linker, indicating // the location of various points in the "Global Section Table". This table is // created by the linker via the Code Red managed linker script mechanism. It // contains the load address, execution address and length of each RW data // section and the execution and length of each BSS (zero initialized) section. //***************************************************************************** extern unsigned int __data_section_table; extern unsigned int __data_section_table_end; extern unsigned int __bss_section_table; extern unsigned int __bss_section_table_end; #else //***************************************************************************** // The following symbols are constructs generated by the linker, indicating // the load address, execution address and length of the RW data section and // the execution and length of the BSS (zero initialized) section. // Note that these symbols are not normally used by the managed linker script // mechanism in Red Suite/LPCXpresso 3.6 (Windows) and LPCXpresso 3.8 (Linux). // They are provide here simply so this startup code can be used with earlier // versions of Red Suite which do not support the more advanced managed linker // script mechanism introduced in the above version. To enable their use, // define "USE_OLD_STYLE_DATA_BSS_INIT". //***************************************************************************** extern unsigned int _etext; extern unsigned int _data; extern unsigned int _edata; extern unsigned int _bss; extern unsigned int _ebss; #endif //***************************************************************************** // Reset entry point for your code. // Sets up a simple runtime environment and initializes the C/C++ // library. //***************************************************************************** //__attribute__ ((section(".after_vectors"))) void Reset_Handler(void) { #ifndef USE_OLD_STYLE_DATA_BSS_INIT // // Copy the data sections from flash to SRAM. // unsigned int LoadAddr, ExeAddr, SectionLen; unsigned int *SectionTableAddr; #else // Use Old Style Data and BSS section initialization. // This will only initialize a single RAM bank. unsigned int * LoadAddr, *ExeAddr, *EndAddr, SectionLen; #endif /* set stack pointer */ __asm(" MSR CPSR_c, #Mode_ABT|I_Bit|F_Bit\n" //Mode_ABT " LDR SP, =_ABT_Stack\n"); __asm(" MSR CPSR_c, #Mode_UNDEF|I_Bit|F_Bit\n" //Mode_UNDEF " LDR SP, =_UND_Stack\n"); __asm(" MSR CPSR_c, #Mode_SVC|I_Bit|F_Bit\n" //Mode_SVC " LDR SP, =_SVC_Stack\n"); __asm(" MSR CPSR_c, #Mode_FIQ\n" //Mode_FIQ " LDR SP, =_FIQ_Stack\n"); __asm(" MSR CPSR_c, #Mode_IRQ\n" //Mode_IRQ " LDR SP, =_IRQ_Stack\n"); __asm(" MSR CPSR_c, #Mode_USR\n" //Mode_USR " LDR SP, =_USR_Stack\n"); #ifndef USE_OLD_STYLE_DATA_BSS_INIT // Load base address of Global Section Table SectionTableAddr = &__data_section_table; // Copy the data sections from flash to SRAM. while (SectionTableAddr < &__data_section_table_end) { LoadAddr = *SectionTableAddr++; ExeAddr = *SectionTableAddr++; SectionLen = *SectionTableAddr++; data_init(LoadAddr, ExeAddr, SectionLen); } // At this point, SectionTableAddr = &__bss_section_table; // Zero fill the bss segment while (SectionTableAddr < &__bss_section_table_end) { ExeAddr = *SectionTableAddr++; SectionLen = *SectionTableAddr++; bss_init(ExeAddr, SectionLen); } #else // Copy the data segment from flash to SRAM. LoadAddr = &_etext; ExeAddr = &_data; EndAddr = &_edata; SectionLen = (void*)EndAddr - (void*)ExeAddr; data_init((unsigned int)LoadAddr, (unsigned int)ExeAddr, SectionLen); // Zero fill the bss segment ExeAddr = &_bss; EndAddr = &_ebss; SectionLen = (void*)EndAddr - (void*)ExeAddr; bss_init ((unsigned int)ExeAddr, SectionLen); #endif #if defined (__USE_CMSIS) SystemInit(); #endif #if defined (__cplusplus) // // Call C++ library initialisation // __libc_init_array(); #endif #if defined (__REDLIB__) // Call the Redlib library, which in turn calls main() __main() ; #else main(); #endif // // main() shouldn't return, but if it does, we'll just enter an infinite loop // while (1) { ; } } //***************************************************************************** // Default exception handlers. Override the ones here by defining your own // handler routines in your application code. //***************************************************************************** //***************************************************************************** // // Processor ends up here if an unexpected interrupt occurs or a specific // handler is not present in the application code. // //***************************************************************************** __attribute__ ((section(".after_vectors"))) void IntDefaultHandler(void) { while(1) { } }