4.3. In a computer, a very common operation is comparing two values. This is often used to set a bit indicating that two quantities are equal or not equal. In many architectures, such as x86 and ARM, these bits are called condition codes. A conditional branch instruction uses these condition codes to determine whether to take a branch or not take a branch (fall thru"). You are assigned to design the compare unit for the TriTip-8- a simple 'non-vegan' -) 8-bit microprocessor. The compare unit takes two operands A[7:01 and B[7:0]. (Funfact - the first video game consoles, such as the Atari 2600 were based on 8-bit microprocessors) 4.3.a - Write a 2-level expression using XOR (A) and NOR for the compare function fcomp which compares two 8 bits numbers A7:01 X70and B[7:070and evaluates to true when A[7:0] and BI7:0] match. 4.3.b - Draw a schematic using for your comparator from part a) using only 2-input XOR, 2-input OR and one final 2-input NOR gate and the minimum number of logic levels. (hint, group the terms using the associative property) 4.3.c -We can recast the answer from part b) using DeMorgan's Theorem on the algebraic representation or use bubble pushing. redraw your schematic using 2-input XOR, 2-input NOR and 2-input NAND gates. Hint, your logic should take the output from the XOR and feed into a 2 input NOR gate You may wish to draw the schematic twice. First replace all the OR gates with NOR, respect the bubbles by adding inverters where needed (odd # of bubbles between and input and an output). Then convert some of the gates to NAND-2 using the hints below to absorb inverters. If you see this Think: (a' b') (ab) AND followed by NOT Think NAND 4.3.d The amazing success of the TriTip-8 results in a contract to build the TriTip-32, a 32-bit microprocessor. Given the following cell delays, estimate the delay for the 32-bit comparator of the TriTip-32. (show how you got your answer) Cell XOR-2 100 ps NAND-270 ps NOR-2 90 ps 4.3. In a computer, a very common operation is comparing two values. This is often used to set a bit indicating that two quantities are equal or not equal. In many architectures, such as x86 and ARM, these bits are called condition codes. A conditional branch instruction uses these condition codes to determine whether to take a branch or not take a branch (fall thru"). You are assigned to design the compare unit for the TriTip-8- a simple 'non-vegan' -) 8-bit microprocessor. The compare unit takes two operands A[7:01 and B[7:0]. (Funfact - the first video game consoles, such as the Atari 2600 were based on 8-bit microprocessors) 4.3.a - Write a 2-level expression using XOR (A) and NOR for the compare function fcomp which compares two 8 bits numbers A7:01 X70and B[7:070and evaluates to true when A[7:0] and BI7:0] match. 4.3.b - Draw a schematic using for your comparator from part a) using only 2-input XOR, 2-input OR and one final 2-input NOR gate and the minimum number of logic levels. (hint, group the terms using the associative property) 4.3.c -We can recast the answer from part b) using DeMorgan's Theorem on the algebraic representation or use bubble pushing. redraw your schematic using 2-input XOR, 2-input NOR and 2-input NAND gates. Hint, your logic should take the output from the XOR and feed into a 2 input NOR gate You may wish to draw the schematic twice. First replace all the OR gates with NOR, respect the bubbles by adding inverters where needed (odd # of bubbles between and input and an output). Then convert some of the gates to NAND-2 using the hints below to absorb inverters. If you see this Think: (a' b') (ab) AND followed by NOT Think NAND 4.3.d The amazing success of the TriTip-8 results in a contract to build the TriTip-32, a 32-bit microprocessor. Given the following cell delays, estimate the delay for the 32-bit comparator of the TriTip-32. (show how you got your answer) Cell XOR-2 100 ps NAND-270 ps NOR-2 90 ps
