For these programming exercises, use only those instructions that have been discussed so far in these notes:
Basic Instructions add div mflo slt, slti addi divu mult sltu, sltiu addiu j multu sra addu lb nor srl and lbu or sub andi lh ori subu beq lhu sb sw bgez lui sh xor bltz lw sll xori bne mfhi PseudoInstructions la lw nop syscall li move sw In the Settings menu of SPIM set Bare Machine OFF, Allow Pseudo Instructions ON, Load Trap File ON, Delayed Branches ON, Delayed Loads ON, Mapped IO ON, Quiet OFF.
Run the programs by loading the trap handler (as explained in the chapter) and clicking SimulatorGo and then OK in the pop-up panel.
Use the
lwandswwith symbolic addresses for loading and storing registers. Use mnemonic register names and use registers in their conventional roles.
Write a program that repeatedly prompts the user for the number of miles traveled and the gallons of gasoline consumed, and then prints out the miles per gallon. Use integer math. Exit when the user enters 0 for the number of miles.
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As in Exercise1, write a program that repeatedly prompts the user for the number of miles traveled and the gallons of gasoline consumed, and then prints out the miles per gallon. Exit when the user enters 0 for the number of miles.
Use fixed-point arithmetic for this.
Multiply input value of miles by 100.
Divide miles by gallons to get miles per gallon.
The answer will 100 times too large.
So divide it by 100 to get whole miles per gallon
in hi and hundredths in lo.
Print out lo followed by "." followed by hi to get
an output that looks like: "32.45 mpg".
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Write a program that asks the user for a string of digits that represent a positive integer. Read in the string using service number 8, the "read string" service. Now convert the string of digits into an integer by the following algorithm:
value = 0;
for each digit starting with the left-most:
{
convert the digit into an integer D by subtracting 0x30
value = value*10 + D
}
You might recognize this as Horner's method. After converting the integer, check if it is correct by writing it out on the simulated monitor using service 1.
Notes: assume that the input is correct (that it contains only digits and can be converted to a 32-bit integer). Be sure to deal properly with the end-of-line character that is at the end of the user's input.
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Write a program that repeatedly asks the user for a scale F or a C (for "Fahrenheit" or "Celsius") on one line followed by an integer temperature on the next line. It then converts the given temperature to the other scale. Use the formulas:
F = (9/5)C + 32 C = (5/9)(F - 32)
Exit the loop when the user types "Q". Assume that all input is correct. For example:
Enter Scale : F Enter Temperature: 32 Celsius Temperature: 0C Enter Scale : C Enter Temperature: 100 Fahrenheit Temperature: 212F Enter Scale : Q done
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