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+# Getting prepared
+
+*Deadline:* Friday, 9/1/2023. 
+
+We will keep the submission open until 9/15/2023 as students may enroll into
+the course late. 
+
+*If you work on a lab computer or UConn AnyWare Desktop, save your files to
+cloud storage like OneDrive. Otherwise, you may lose your files.*
+
+## Learning Objectives
+
+*   Run a RISC-V programs in RARS. 
+
+*   Submit code in Gradescope.
+
+*   Conversion of non-negative numbers in one radix to another.
+
+*   Take a quiz in HuskyCT.
+
+## Description
+
+### Task 1
+
+Follow the instructions on [this
+page](https://github.com/zhijieshi/cse3666/blob/master/misc/rars.md) to install
+RARS and run RISC-V programs in RARS. 
+
+Download `lab0.s`. The RARS instructions page mentioned in the previous
+paragraph has a section about "Download files from GitHub". The page also has a
+link to more [RISC-V
+examples.](https://github.com/zhijieshi/cse3666/tree/master/rv-examples).
+
+Modify the `msg` string in lab0.s so the program prints the following. There is
+a newline, but no space, after the ending dot.
+
+    Hello, welcome to CSE 3666. The best season is here.
+
+Submit revised `lab0.s` in Gradescope. There is a link in HuskyCT. The
+submitted filename must be `lab0.s`. It is case sensitive. The system does NOT
+accept names like `Lab0.s`.
+
+### Task 2
+
+Study the slides in `lab0-numbers.pdf` to learn/review conversion of numbers in
+different radices. 
+
+*   Binary to decimal.
+*   Decimal to binary.
+*   Hexadecimal to decimal.
+*   Decimal to hexadecimal.
+
+Practice on [this page](https://zhijieshi.github.io/cse3666/binarynumbers/).
+For now, you can click the Config button and uncheck "Bits are signed".
+
+## Deliverables
+
+Submit `lab0.s` in Gradescope and complete lab0-test in HuskyCT. 
+
+The submission pages will be created in the first week of the semester.
+
diff --git a/lab0/lab0.s b/lab0/lab0.s
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+#       CSE 3666 Lab 0
+
+#       Anything after # is comments.
+
+        # .data starts data segments
+        .data
+        # msg is a label in data segment 
+        # .asciz specifies an ASCII string ends with a NUL character
+        # we can also use ".string", instead of ".asciz"
+msg:    .asciz  "Hello, welcome to CSE 3666.\n"
+
+        # .text starts code segments
+        .text
+
+        # define a label, in code segment
+main:   
+        lui     a0, 0x10010     # a0 = the address of msg. hard-coded
+        addi    a7, zero, 4     # a7 = 4, the system call number for printing a string
+        ecall                   # system call
+
+        # system call 10: exit with code 0
+        addi    a7, zero, 10    # a7 = 10
+        ecall                   # system call