Step A. Use GPIO to control the LED

The microblaze processor is configured in part 1 ti connect to the LED viaGPIO. You can read from the GPIO and write to the GPIO. In this case, only writing is necessary.
Include header file "xgpio_1.h" to use the GPIO functions.
When using the GPIO, first you have to specify whether a bit is for input or output. Use the following to set it:

XGpio_Initialize(BASEADDR, DEVICE_ID); XGpio_mSetDataDirection(BASEADDR, 1, 0x00000000);

The first parameter is the address mapped to the GPIO. The second parameter is the GPIO channel, which is 1 in this case. The third parameter is for setting the read/write mode of individual bit, 1 means for read and 0 means for write.
You can then write to the GPIO using the following function:

XGpio_mSetDataReg(BASEADDR, 1, data);

Write an application that turn on the LED lights one at a time from left to right (or any pattern of your choice). The lights should change every half a second. You can use a busy waiting loop here to wait for time.

Step B.Use Timer and Interrupt Handler

Timer can be used to generate interrupt in regular intervals. A timer is setup in part 1 with interrupt enabled. When the timeout expired, a interrupt will be generated to your microblaze processor. To setup a interrupt handler, use the following function:

#include "xtmrctr_1.h" #include "xintc_1.h" /* Enable MicroBlaze interrupts */ microblaze_enable_interrupts(); /* Register the interrupt handler in the vector table */ XIntc_RegisterHandler(INTC_BASEADDR, INTR, (XInterruptHandler)handler, (void*)BASEADDR); /* Start the interrupt controller */ XIntc_mMasterEnable(INTC_BASEADDR);

to set the timer:

/* Set the number of cycles the timer counts before interrupting */ XTmrCtr_mSetLoadReg(BASEADDR, 0, time_tick); /* Reset the timers, and clear interrupts */ XTmrCtr_mSetControlStatusReg(TIMER_BASEADDR, 0, XTC_CSR_INT_OCCURED_MASK | XTC_CSR_LOAD_MASK ); /* Enable interrupt requests in the interrupt controller */ XIntc_mEnableIntr(INTC_BASEADDR, TIMER_INTERRUPT_MASK); /* Start the timers */ XTmrCtr_mSetControlStatusReg(TIMER_BASEADDR, 0, XTC_CSR_ENABLE_TMR_MASK | XTC_CSR_ENABLE_INT_MASK | XTC_CSR_AUTO_RELOAD_MASK | XTC_CSR_DOWN_COUNT_MASK);

interruptHander is a function with the following function declaration:

void handler(void * baseaddr_p);

and for timer interrupt, you can use the following template:

void timer_int_handler(void * baseaddr_p) { unsigned int csr; /* Read timer 0 CSR to see if it requested the interrupt */ csr = XTmrCtr_mGetControlStatusReg(BASEADDR, 0); if (csr & INT_OCCURED_MASK) { /* handler interrupt here*/ } /* Clear the timer interrupt */ XTmrCtr_mSetControlStatusReg(BASEADDR, 0, csr); }

? Copy your code from step A and modify it to use the timer instead of busy-waiting loop.

Step C.Use UART to read character from serial port

? The microblaze processor is configured in part 1 to connect to the serial port viaUARTand use interrupt. When a character is entered into hyperterminal, the character is sent to the UART and an interrupt is generated. You can setup a interrupt handler for UART interrupt just like you did for timer interrupt, and read the characters one by one from the UART using the following function:

#include "xuartlite_1.h" XUartLite_mIsReceiveEmpty(BASEADDR) is false when there is data waiting to be read XUartLite_RecvByte(BASEADDR) return one character (char)

enable UART interrupt

/* Enable interrupt requests in the interrupt controller */ XIntc_mEnableIntr(INTC_BASEADDR, TIMER_INTERRUPT_MASK | UART_INTERRUPT_MASK); /* Enable UART interrupts */ XUartLite_mEnableIntr(BASEADDR);

Copy your code from step B and modify it to decrease the time between LED changes by half if a '[' is received and increase the time two times if a ']' is received.