i am facing a wierd problem.. My MCU P89V51RD2BN resets during Execution... i am a college student and a beginner Here so i dont know the Advanced Programming methods i would also inform that..
i have a recursive function , a warning is issued by the compiler for the same. but....
earlier this was not a problem but since i have modified some of the Sub-Routines for 16Bit Data this Problem has come up, i need those functions to be 16 bit because of the limitation of the ALU i was earlier using 8bit and leaving most of the Task to Assumption which i cannot do so now..
i would also state that the Problem occurs in a fumction at a point when i call 2 functions in the same code, these themselves call around 5 sub-routines each but that wasnt a problem earlier (before i used the 16bit return type sub-routines).
now i found something in the manual stating reentrant Functions, but i really dont know how to use it
i used it like this
void Home_Screen_Instance() reentrant { ------------ } Do i need to use the keyword "reentrant" in the Function Decleration too? but that didnt help either but the compilers shows an error Home_Screen_Instance : redefinition. Target Not Created
this was the first of a kind problem that i encountered, my MCU is resetting itself for sure(i checked that with a dummy subroutine of blinking LED) and it is not because of the watchdog timer, i am sure about that too..
so whats the Problem here?
is the Stack overflowing??? or there is any other reason behind this? should i revert back to the 8bit versions of my subroutine (without any other choice)? is it because of the recursive nature of the function H0me_screen_instance?
Related Data:
The Program is Display intensive, i mean there are a lot of Strings to be displayed and they are stored beforehand in XDATA, message shown during sucessfull compilation, (still resets) Program Size: data 9.4 xdata 252 code 9514 creating hex-----blah blah blah---- 0 Error(s) 65 Warning(s)
i was passing Parameters to the function because at some places The Space available at the LCD is limited its like XXXXXW 'X'is the available space for user input while the rest has been occupied by other text, so if the input is unbound in terms of number of digits it may overwrite, other strings on the LCD.
Secondly, one of the parameters is "bit show" which is used to control if the characters being typed need to be visible at the LCD.
i had doubts implementing it as a stack...but my main reason was the unknown Size(number of Characters) for the input, that's why i let it be a stack of 10 Characters, so that the same stack can be used if i made some other Sub-Routine which required Stack implementation.
and one more question... i was searching for books on Programming both general Programming and Embedded Programming and of these the best i found was Embedded C by Micheal J Pont The art of Programming by Knuth
can you suggest any other reads apart from these.. the book by muhaamad ali mazidi is one of my textbook
I do know what you used the parameters for.
But the interesting question is why you think you need the parameter "BreakC".
yeah... i didnt realize that was actually taking extra work all the time, i really didnt require BreakC... ill define a constant for that, it would atleast reduce the number of parameters
here i got another problem, the code in between the Stars is being bypassed completely, i didnt understand it first but then i started inserting dummy routines in between codes and found out that the code (in Bold) is being completely bypassed every time.
Home_Screen() //Draws the Home Screen Keypad_Instance() //Has been already posted in this thread Check_Lock1() //Checks if the code entered is correct or not and opens the lock if true
void Start() { Lock_State = Closed; do { Home_Screen(); while(Keypad_Input() == False);// Wait for a key to be pressed. //******************************************************************************************* while(Lock_State == Closed) { Lock_Screen(); Keypad_Instance(5,2,8,0,'C'); // 5 character password at pos 2,8, Hidden and 'C' is the break Character Check_Lock1(); //Check the Password, if true then Lock_State=Open if(Lock_State == Open)// Lock is Open break; else { LCD_Cursor_XY(3,7); LCD_Text("RETRY !!!"); //on entering Wrong Password } } Main_Menu1_Instance(); //********************************************************************************************* }while(1); }
i didnt get it, why is this not working, Note: i tried implemnting the Code in italics in a do-While loop, but the same problem creeped up, this was not a problem when i had those recursive functions LOL ;P!!