Problem on Build a Project: Build Errror: Undefined Reference to "tenthSecond","oneSecond"....

Dear All:

Just starting to say that I am new on PSOC Creator and maybe you can tell me what is wrong with the code below. When I try to build the SW that I attache (timing.h, timing.c and main.c)  I get the error above. Anyhelp will be appreciated. Thanks in advance to all.

Regards,Joaquin

-----timing.h code:-----

#include <project.h>
#include <device.h>

/******************************************
*       Global Variables
******************************************/

extern uint8 milliSecond;
extern uint8 tenthSeconds;
extern uint8 oneSecond;
extern uint8 tenSeconds;

/******************************************
*   Function Prototypes
******************************************/

/******************************************
*   Function Name: InitTiming()
*******************************************
void InitTiming(void);
//[] END OF FILE

---Code for timing.c:---

#include <device.h>
#include <timing.h>
#include "stdio.h"
#include "stdint.h"

/******************************************
*   Global Variables
******************************************/
//Event flags for each of the time periods
uint8 tenthSeconds= 0U;
uint8 oneSecond= 0U;
uint8 tenSeconds= 0u;

/******************************************
*       Private Functions
******************************************/
/******************************************
*Function Name: TimeISR()
******************************************
*******************************************/
static CY_ISR(TimerIsr)
{
   
// Counters for the longer periods
static uint8  tenthSecondsCount= 0U;
static uint16 oneSecondCount= 0U;
static uint16 tenSecondsCount= 0U;
   
(void)PWM_Timer_STATUS;
//milliSecond = 1U; // Always set the millisecond global event flag

//Check if a tenth second has passed
if (tenthSecondsCount > 99U)
{    tenthSeconds = 1U;//tenthSecond global event flag
    tenthSecondsCount=0;
}
else
    tenthSecondsCount++;

//Check if a second has passed
if (oneSecondCount > 999U)
{
    oneSecond = 1U; //oneSecond global event flag
    oneSecondCount=0;
}
else
    oneSecondCount++;

//Check if a tenseconds has passed
if (tenSecondsCount > 9999U)
{
    tenSeconds = 1U; //tenSeconds global event flag
    tenSecondsCount=0;
}
else
    tenSecondsCount++;

} //End of TimeIsr();

/******************************************
*       Global Functions
******************************************/

/******************************************
*Function Name: InitTiming()
******************************************/
void InitTiming(void)
{
    isr_PWM_Start();
    isr_PWM_SetVector(TimerIsr);
} // End of InitTiming()


/* [] END OF FILE */

---Code for main C---

#include <project.h>
#include <device.h>
#include <stdio.h>
#include "timing.h"
#include "UART.h"

#define LCD_NUM_COLUMNS (16u)

uint8 datos[3]= {0x65, 0x66, 0x67};

void main()
{  
    char8 ch;       /* Data received from the Serial port */
    uint8 count = 0u;
    uint8 pos = 0u;

    CyGlobalIntEnable; /* Enable all interrupts by the processor. */
    InitTiming();       // Interrupt
    PWM_Timer_Start();  //Source of interrupt

    LCD_Char_1_Start();
    UART_OXI_Start();
    CyDelay(30); // just to be sure the UART is up and running
    isr_1_Start();      /* Initializing the ISR */
    UART_OXI_ClearRxBuffer();//Clear RXbuffer

    while(1)
    {
        /* Check the UART status */
        ch = UART_OXI_GetChar();

        /* If byte received */
        if(ch > 0)
        {
            count++;       
            /* If the count value reaches the count 16 start from first location */
            if(count % LCD_NUM_COLUMNS == 0u)
            {
                pos = 0u; /* resets the count value */
                /* Display will be cleared when reached count value 16 */
                LCD_Char_1_WriteControl(LCD_Char_1_CLEAR_DISPLAY);
            }

            LCD_Char_1_Position(0u, pos++);
            LCD_Char_1_PutChar(ch);         /* Print the received character */

            LCD_Char_1_Position(1u, 0u);
            LCD_Char_1_PrintInt8(count);    /* Prints the count in the LCD */
                        
            UART_OXI_SendData(ch);/* Sending the data to Hyperterminal */
         
        }
       
    }
}


/* [] END OF FILE */