diff --git a/Group21_Lab06_Task2/main.c b/Group21_Lab06_Task2/main.c
index b78af4e..bcf15c4 100644
--- a/Group21_Lab06_Task2/main.c
+++ b/Group21_Lab06_Task2/main.c
@@ -6,3 +6,14 @@ volatile int duty = 50; // Initial duty cycle
 volatile bool buttonPressed = false; // Track button state
 volatile uint32_t pressDuration = 0; // Track how long the button is pressed
 const long int PWM_PERIOD = 1000000; // Period for 100kHz in microseconds (10ms)
+#define STCTRL *((volatile uint32_t *) 0xE000E010) // Control and status
+#define STRELOAD *((volatile uint32_t *) 0xE000E014) // Reload value
+#define STCURRENT *((volatile uint32_t *) 0xE000E018) // Current value
+
+#define COUNT_FLAG (1 << 16) // Bit 16 of CSR automatically set to 1
+#define ENABLE (1 << 0) // Bit 0 of CSR to enable the timer
+#define CLKINT (1 << 2) // Bit 2 of CSR to specify CPU clock
+#define CLOCK_HZ 16000000 // Clock frequency of EK-TM4C123GXL
+#define INTEN (1 << 1) // Bit 1 of CSR to enable interrupt
+#define SYSTICK_RELOAD_VALUE(us) ((CLOCK_HZ / 1000000) * (us) - 1) // SysTick reload value in microseconds based on clock frequency
+