1 /*********************************************************************
2 *
3 * Generic Exception Handler
4 *
5 *********************************************************************
6 * FileName: exceptions.c
7 * Dependencies:
8 *
9 * Processor: PIC32
10 *
11 * Complier: MPLAB C32
12 * MPLAB IDE
13 * Company: Microchip Technology, Inc.
14 * Author: Darren Wenn
15 *
16 * Software License Agreement
17 *
18 * The software supplied herewith by Microchip Technology Incorporated
19 * (the “Company”) for its PIC32/PIC24 Microcontroller is intended
20 * and supplied to you, the Company’s customer, for use solely and
21 * exclusively on Microchip PIC32/PIC24 Microcontroller products.
22 * The software is owned by the Company and/or its supplier, and is
23 * protected under applicable copyright laws. All rights are reserved.
24 * Any use in violation of the foregoing restrictions may subject the
25 * user to criminal sanctions under applicable laws, as well as to
26 * civil liability for the breach of the terms and conditions of this
27 * license.
28 *
29 * THIS SOFTWARE IS PROVIDED IN AN “AS IS” CONDITION. NO WARRANTIES,
30 * WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED
31 * TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
32 * PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,
33 * IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR
34 * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
35 *
36 *
37 *
38 ********************************************************************/
39
40 #include <p32xxxx.h>
41
42 // declared static in case exception condition would prevent
43 // auto variable being created
44 static enum {
45 EXCEP_IRQ = 0, // interrupt
46 EXCEP_AdEL = 4, // address error exception (load or ifetch)
47 EXCEP_AdES, // address error exception (store)
48 EXCEP_IBE, // bus error (ifetch)
49 EXCEP_DBE, // bus error (load/store)
50 EXCEP_Sys, // syscall
51 EXCEP_Bp, // breakpoint
52 EXCEP_RI, // reserved instruction
53 EXCEP_CpU, // coprocessor unusable
54 EXCEP_Overflow, // arithmetic overflow
55 EXCEP_Trap, // trap (possible divide by zero)
56 EXCEP_IS1 = 16, // implementation specfic 1
57 EXCEP_CEU, // CorExtend Unuseable
58 EXCEP_C2E // coprocessor 2
59 } _excep_code;
60
61 static unsigned int _epc_code;
62 static unsigned int _excep_addr;
63
64 #include <rtthread.h>
65 // this function overrides the normal _weak_ generic handler
_general_exception_handler(void)66 void _general_exception_handler(void)
67 {
68 asm volatile("mfc0 %0,$13" : "=r" (_excep_code));
69 asm volatile("mfc0 %0,$14" : "=r" (_excep_addr));
70
71 _excep_code = (_excep_code & 0x0000007C) >> 2;
72
73 rt_kprintf("\r\n_excep_code : %08X\r\n",_excep_code);
74 rt_kprintf("_excep_addr : %08X\r\n",_excep_addr);
75 switch(_excep_code)
76 {
77 case EXCEP_IRQ:rt_kprintf("interrupt\r\n");break;
78 case EXCEP_AdEL:rt_kprintf("address error exception (load or ifetch)\r\n");break;
79 case EXCEP_AdES:rt_kprintf("address error exception (store)\r\n");break;
80 case EXCEP_IBE:rt_kprintf("bus error (ifetch)\r\n");break;
81 case EXCEP_DBE:rt_kprintf("bus error (load/store)\r\n");break;
82 case EXCEP_Sys:rt_kprintf("syscall\r\n");break;
83 case EXCEP_Bp:rt_kprintf("breakpoint\r\n");break;
84 case EXCEP_RI:rt_kprintf("reserved instruction\r\n");break;
85 case EXCEP_CpU:rt_kprintf("coprocessor unusable\r\n");break;
86 case EXCEP_Overflow:rt_kprintf("arithmetic overflow\r\n");break;
87 case EXCEP_Trap:rt_kprintf("trap (possible divide by zero)\r\n");break;
88 case EXCEP_IS1:rt_kprintf("implementation specfic 1\r\n");break;
89 case EXCEP_CEU:rt_kprintf("CorExtend Unuseable\r\n");break;
90 case EXCEP_C2E:rt_kprintf("coprocessor 2\r\n");break;
91 default : rt_kprintf("unkown exception\r\n");break;
92 }
93
94 while (1) {
95 // Examine _excep_code to identify the type of exception
96 // Examine _excep_addr to find the address that caused the exception
97 }
98 }
99