6 years, 9 months ago.

HardFault occurs when fopen() is called after EthernetInterface.connect(); (with mbed OS 5.4~5.8)

Hi,

I'm trying to make a program with which to make LPC1768 a kind of a file server, which communicate with devices over Ethernet, and read/write text files in ther local drive of LPC1768.

I'm using :

• LPC1768
• mbed OS 5 (5.4.7 ~ 5.8.1)
• Online ARM compiler
• EthernetInterface (Class)
• LocalFileSystem (Class)

LPC1768 is conneting to:

• PC with USB
• A router with LAN cable

and I have found that my mbed freezes when fopen() after EthernetInterface-instance.connect(). I extrated the part which has something wrong from my program. Following code can reproduce the error I had:

#include "mbed.h"
#include "EthernetInterface.h"
 
LocalFileSystem local("local");
void func();
EthernetInterface *net;
 
int main()
{
    func();
    net = new EthernetInterface();
    func();
    if(net->connect()) {
        printf("Error!@EthernetInterface::connect()\r\n");
    } else {
        printf("IP Address is %s\r\n", net->get_ip_address());
    }
    func();
}
 
 
void func()
{
    static int i = 1;
    printf("-------test of fopen()#%d----\r\n", i);
    if(fopen("/local/test.txt", "r")==NULL)
        printf("File could not open\r\n");
    else
        printf("File was opened successfully.\r\n");
    i++;
}

When I connect the LPC1768 to a router with RJ45(LAN), and also to my PC with USB, and then I execute this program, I get following result on the console on my PC.

-------test of fopen()#1----
File was opened successfully.
-------test of fopen()#2----
File was opened successfully.
IP Address is 192.168.11.3
-------test of fopen()#3----                //printf() just before if-clause in func() does work
//here, LPC1768 hang up @fopen() just before printf() in if-clause in func()

Can you reproduce the error? or Can you tell me what did I do wrong? or Do some libraries have bugs? or Is there another new API to handle the local drive of LPC1768?

I will appreciate any comment!!! Thanks!!!

-------test of fopen()#1----
File was opened successfully.
-------test of fopen()#2----
File was opened successfully.
IP Address is 192.168.11.3
-------test of fopen()#3----
File was opened successfully.                            //DOESN'T freeze

-------test of fopen()#1----

File was opened successfully.

-------test of fopen()#2----

File was opened successfully.

IP Address is 192.168.11.3

-------test of fopen()#3----


++ MbedOS Fault Handler ++

FaultType: HardFault

Context:
R0   : 00000001
R1   : 10002618
R2   : 00000000
R3   : 00003F00
R4   : 00000005
R5   : 1000263C
R6   : 00000000
R7   : 10000B8C
R8   : 00000000
R9   : FFFFFFFF
R10  : 00000000
R11  : 00000000
R12  : 000041BD
SP   : 10002618
LR   : 0000D0CB
PC   : 0000D0D0
xPSR : 01000000
PSP  : 100025F8
MSP  : 10007FD8
CPUID: 412FC230
HFSR : 80000000
MMFSR: 00000000
BFSR : 00000000
UFSR : 00000000
DFSR : 0000000A
AFSR : 00000000
SHCSR: 00000000

Thread Info:
Current:
State: 00000002 EntryFn: 0000CDCD Stack Size: 00001000 Mem: 100016A8 SP: 10002550
Next:
State: 00000002 EntryFn: 0000CDCD Stack Size: 00001000 Mem: 100016A8 SP: 10002550
Wait Threads:
State: 00000083 EntryFn: 0000BFED Stack Size: 00000300 Mem: 10000610 SP: 100008A0
Delay Threads:
State: 00000043 EntryFn: 000115C1 Stack Size: 000004B0 Mem: 10002C08 SP: 10003020
Idle Thread:
State: 00000001 EntryFn: 0000B521 Stack Size: 00000200 Mem: 10000410 SP: 100005C8

-- MbedOS Fault Handler --