AVR Freaks

Added the following code:

			"POP     {r0}\n\t"					// Pop new task's FPEXC
			"VMSR    FPEXC, r0\n\t"

EDITED: forgot to mention that the floating point error is still there.

Maybe I will not have to resort to the debugger, I found two or three errors in the function that creates the task.  See below, I'll not be able to test it until tomorrow.  Here's hoping it works.

struct task_ctrl_obj * api_program(void(*task)(void), char const * name, void * variable_pass, unsigned int mpu_mem, unsigned char priority, unsigned char ceiling ){

    api_system_gateway();

    if(priority > 63){
        return(0);
    }

    struct task_ctrl_obj * tcb;

    tcb = safe_malloc(sizeof(struct task_ctrl_obj));            // Allocate Memory for the Task Ctrl Block, used by the Kernel to manage the Task

    memset(tcb, 0x00, sizeof(struct task_ctrl_obj));

    if(tcb == NULL){
        return(NULL);
    }




    unsigned int stack;

    // Allocate Memory for the Stack
    tcb->mpu_base_mem_addr = safe_malloc(mpu_mem * sizeof(int));
    tcb->stack_allocation = (unsigned char *)tcb->mpu_base_mem_addr;


    // find the number of bytes allocated
    stack = mpu_mem * sizeof(int);


    if(tcb->mpu_base_mem_addr == NULL){
        safe_free(tcb);
        return(NULL);
    }

    // PointStack to the end of the memory structure, Stack grows downwards
    unsigned int * cpu_context = (unsigned int *)(stack + tcb->mpu_base_mem_addr);

    /* Align stack pointer.                                 */
    cpu_context = (unsigned int *)((unsigned int)(cpu_context) & 0xFFFFFFF8u);

    tcb->task_status = DORMANT;    // Initial State of all Tasks is DORMANT


    /*
     *    Register task name with operating system
     */
    tcb->name[0] = '\0';

    //if task name has been specified then load the name into the system
    if(strlen(name)){

        struct task_id * log = safe_malloc(sizeof(struct task_id ));
        log->id = tcb;

        int i = 0;    while(* name != '\0'){

                // copy the name
                tcb->name[i] = * name; log->name[i++] = * name; name++;
        }

        // tidy up strings by nulling the end
        tcb->name[i] = '\0'; log->name[i] = '\0';
        add_system_name(log);
    }


    /*
     * Signal Setup
     */
    // Setup Signal Receive Buffer, also associated with TCB
    tcb->signals = safe_malloc(sizeof(struct ipc_signal_sent));
    if(tcb->signals == NULL){

        safe_free(tcb);
        safe_free(tcb->stack_allocation);
        safe_free((struct ipc_signal_obj *)tcb->signal_management);
        return(NULL);
    }

    tcb->signal_management->nr_signal_registered = 0;
    tcb->signals->nr_signal_received = 0;



    /*
     * Setup tcb priority
     */
    tcb->delta_priority   = priority;                                    // Set Task Priority
    tcb->ceiling_priority = ceiling;
    tcb->default_priority = priority;                                    // Set Base Priority, used by the Priority inversion protocol


    unsigned int program = (unsigned int)task & ~1u; /* Mask off lower bit in case task is thumb mode        */                                      /* Mask off lower bit in case task is thumb mode        */
    /*
     * Setup general purpose registers
     */
     * cpu_context-- = (unsigned int) program;                                            /* PC                                                    */
     * cpu_context-- = (unsigned int) internal_task_destructor;                            /* LR: Supervisor mode                                       */
     * cpu_context-- = (unsigned int) 0x00000011;                                       /* R1`                                                        */
     * cpu_context-- = (unsigned int) 0x00000010;                                       /* R10                                                        */
     * cpu_context-- = (unsigned int) 0x00000009;                                       /* R09                                                           */
     * cpu_context-- = (unsigned int) 0x00000008;                                        /* R8                                                           */
     * cpu_context-- = (unsigned int) 0x00000007;                                       /* R7                                                        */
     * cpu_context-- = (unsigned int) 0x00000006;                                        /* R6                                                           */
     * cpu_context-- = (unsigned int) 0x00000005;                                       /* R5                                                        */
     * cpu_context-- = (unsigned int) 0x00000004;                                       /* R4                                                        */
     * cpu_context-- = (unsigned int) 0x00000003;                                       /* R3                                                        */
     * cpu_context-- = (unsigned int) 0x00000002;                                       /* R2                                                        */
     * cpu_context-- = (unsigned int) 0x00000001;                                       /* R1                                                        */
     * cpu_context-- = (unsigned int) 0x00000000;                                       /* R0  ARGUMENT PASS                                                         */
     * cpu_context-- = (unsigned int) variable_pass;                                    /* status regsiter                             */


    #define  ARM_MODE_ARM           0x00000200u
    #define  ARM_MODE_THUMB         0x00000220u

    #define  ARM_SVC_MODE_THUMB    (0x00000013u + ARM_MODE_THUMB)
    #define  ARM_SVC_MODE_ARM      (0x00000013u + ARM_MODE_ARM)


     // Setup Status registers
     if ((task & 0x01u) == 0x01u) {                   /* See if task runs in Thumb or ARM mode                */
        * cpu_context-- = ARM_SVC_MODE_THUMB;                  /* CPSR  (Enable IRQ and FIQ interrupts, THUMB-mode)    */
     }
     else {
        * cpu_context-- = ARM_SVC_MODE_ARM;                    /* CPSR  (Enable IRQ and FIQ interrupts, ARM-mode)      */
     }

     /*
      *    Setup Floating Point registers
      **/
     * cpu_context-- = (unsigned int)0x00000000;         /* Initialise Floating point status & control register  */

     // floating point reegisters
     for (int i = 0; i < 32; i++)
         * cpu_context-- = (unsigned int)0x00000000;    /* Initialise general-purpose Floating point registers  */

     // floating point execution register
     * cpu_context = (unsigned int)0x40000000;           /* Initialise Floating-Point Exception Register (Enable)*/


    // Insert Newly created task on to the Kernel
    internal_kernel_insert_task(tcb);                                            // insert task ctrl block unto Kernel Schedular


    tcb->stack_ptr = (unsigned char *)cpu_context;                                                    // Store Stack pointer unto the task ctrl block
    return(tcb);                                                        // Return Handle to the newly Created Task
}