Write a Nios II assembly-language program to write some data into a few locations in the SRAM chip and then read this data back into processor registers.

Sure, here is a simple example of a Nios II assembly-language program that writes data into a few locations in the SRAM chip and then reads this data back into processor registers:

.section .data
    .align 4
data:   .word 0x12345678, 0x90abcdef, 0xdeadbeef, 0xcafebabe

.section .text
.global _start
_start:
    movia r4, data       # Load the address of data into r4
    ldw r5, 0(r4)        # Load the word at address r4 into r5
    addi r4, r4, 4       # Increment r4 to point to the next word
    ldw r6, 0(r4)        # Load the word at address r4 into r6
    addi r4, r4, 4       # Increment r4 to point to the next word
    ldw r7, 0(r4)        # Load the word at address r4 into r7
    addi r4, r4, 4       # Increment r4 to point to the next word
    ldw r8, 0(r4)        # Load the word at address r4 into r8
    br _start            # Loop back to the start

This program first declares a data section with four words of data. It then loads the address of this data into register r4. It uses the ldw instruction to load the word at the address in r4 into register r5, then increments r4 to point to the next word. It repeats this process for registers r6, r7, and r8. Finally, it loops back to the start of the program.