Logic Design, Part 5
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0:06Recap and set the stage for the day continuing with the simulator
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0:06Recap and set the stage for the day continuing with the simulator
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0:06Recap and set the stage for the day continuing with the simulator
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2:30Check out the graph of Example7, our adder
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2:30Check out the graph of Example7, our adder
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2:30Check out the graph of Example7, our adder
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3:32Simulate our adder
3:32Simulate our adder
3:32Simulate our adder
5:16Verify our adder simulation using python's own addition functionality
5:16Verify our adder simulation using python's own addition functionality
5:16Verify our adder simulation using python's own addition functionality
6:41Run it and fail to hit our verification assertion, with a few words on this brute-force verification
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6:41Run it and fail to hit our verification assertion, with a few words on this brute-force verification
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6:41Run it and fail to hit our verification assertion, with a few words on this brute-force verification
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8:33Simulate our subtraction circuit
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8:33Simulate our subtraction circuit
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8:33Simulate our subtraction circuit
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9:14Run it to find that our subtraction works too
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9:14Run it to find that our subtraction works too
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9:14Run it to find that our subtraction works too
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9:36Simulate our less-than comparison circuit
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9:36Simulate our less-than comparison circuit
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9:36Simulate our less-than comparison circuit
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10:37Run it to find that our less-than comparison does not work
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10:37Run it to find that our less-than comparison does not work
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10:37Run it to find that our less-than comparison does not work
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15:06rygorous carry = below, (i.e. unsigned less than). Definitely not <=. Argh, no, I'm thinking x86. x86 CMP is a SUB which sets the carry flag to "borrow", which is !carry, i.e. you need to invert. Your carry is unsigned >=, as in, regular (non-inverted) carry is
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15:06rygorous carry = below, (i.e. unsigned less than). Definitely not <=. Argh, no, I'm thinking x86. x86 CMP is a SUB which sets the carry flag to "borrow", which is !carry, i.e. you need to invert. Your carry is unsigned >=, as in, regular (non-inverted) carry is
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15:06rygorous carry = below, (i.e. unsigned less than). Definitely not <=. Argh, no, I'm thinking x86. x86 CMP is a SUB which sets the carry flag to "borrow", which is !carry, i.e. you need to invert. Your carry is unsigned >=, as in, regular (non-inverted) carry is
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15:10Negate the result of the less-than comparison in Example10
15:10Negate the result of the less-than comparison in Example10
15:10Negate the result of the less-than comparison in Example10
15:58Run it to find that our inverted less-than comparison succeeds
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15:58Run it to find that our inverted less-than comparison succeeds
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15:58Run it to find that our inverted less-than comparison succeeds
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16:19Respecify Example10 as greater-than-or-equal-to, and simulate its signed comparison
16:19Respecify Example10 as greater-than-or-equal-to, and simulate its signed comparison
16:19Respecify Example10 as greater-than-or-equal-to, and simulate its signed comparison
18:29Run it to find that our signed greater-than-or-equal-to comparison fails
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18:29Run it to find that our signed greater-than-or-equal-to comparison fails
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18:29Run it to find that our signed greater-than-or-equal-to comparison fails
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20:29Enable join() to interpret NOT as an unsigned operation
20:29Enable join() to interpret NOT as an unsigned operation
20:29Enable join() to interpret NOT as an unsigned operation
21:35Change our geus simulation test to assert that x < y (i.e. less-than), and find that it passes
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21:35Change our geus simulation test to assert that x < y (i.e. less-than), and find that it passes
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21:35Change our geus simulation test to assert that x < y (i.e. less-than), and find that it passes
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21:53Understanding the lts comparison and bitwise negation before sign-extension of the second operand
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21:53Understanding the lts comparison and bitwise negation before sign-extension of the second operand
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21:53Understanding the lts comparison and bitwise negation before sign-extension of the second operand
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24:08Set up to cover fast adders
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24:08Set up to cover fast adders
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24:08Set up to cover fast adders
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25:31Understanding ripple-carry adder performance, with a mention of FO4
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25:31Understanding ripple-carry adder performance, with a mention of FO4
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25:31Understanding ripple-carry adder performance, with a mention of FO4
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28:40Speculative execution, and carry-select addition
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28:40Speculative execution, and carry-select addition
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28:40Speculative execution, and carry-select addition
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31:15Set up to easily instantiate different sized adders
31:15Set up to easily instantiate different sized adders
31:15Set up to easily instantiate different sized adders
33:34Define Example11 as a divide-and-conquer ripple-carry adder
33:34Define Example11 as a divide-and-conquer ripple-carry adder
33:34Define Example11 as a divide-and-conquer ripple-carry adder
37:08Simulate Example11 to see that it works
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37:08Simulate Example11 to see that it works
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37:08Simulate Example11 to see that it works
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37:31Define Example12 using speculative execution on Example11 to form a carry-select adder
37:31Define Example12 using speculative execution on Example11 to form a carry-select adder
37:31Define Example12 using speculative execution on Example11 to form a carry-select adder
38:48Simulate Example12 to see that it works
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38:48Simulate Example12 to see that it works
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38:48Simulate Example12 to see that it works
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39:21Understanding why the carry-select adder is faster than ripple-carry
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39:21Understanding why the carry-select adder is faster than ripple-carry
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39:21Understanding why the carry-select adder is faster than ripple-carry
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42:16Introduce conditional_sum_adder()
42:16Introduce conditional_sum_adder()
42:16Introduce conditional_sum_adder()
42:45cubercaleb data.medicare.gov.json?
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42:45cubercaleb data.medicare.gov.json?
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42:45cubercaleb data.medicare.gov.json?
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42:52Implement conditional_sum_adder()
42:52Implement conditional_sum_adder()
42:52Implement conditional_sum_adder()
45:41Check out the graph of Example12, the carry-select adder
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45:41Check out the graph of Example12, the carry-select adder
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45:41Check out the graph of Example12, the carry-select adder
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46:26Define Example13 as a conditional-sum adder
46:26Define Example13 as a conditional-sum adder
46:26Define Example13 as a conditional-sum adder
48:25Check out the graph of Example13, the conditional-sum adder
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48:25Check out the graph of Example13, the conditional-sum adder
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48:25Check out the graph of Example13, the conditional-sum adder
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49:02Instantiate a 16-bit conditional-sum adder, and check out its graph
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49:02Instantiate a 16-bit conditional-sum adder, and check out its graph
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49:02Instantiate a 16-bit conditional-sum adder, and check out its graph
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50:28Simulate our conditional-sum adder
50:28Simulate our conditional-sum adder
50:28Simulate our conditional-sum adder
51:46Run it to find that the conditional-sum adder does not work
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51:46Run it to find that the conditional-sum adder does not work
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51:46Run it to find that the conditional-sum adder does not work
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54:14Investigate the possibility that the simulator is not correctly masking
54:14Investigate the possibility that the simulator is not correctly masking
54:14Investigate the possibility that the simulator is not correctly masking
1:04:45Step through compile() to see how it treats our operands, and find that the operands don't have the same length
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1:04:45Step through compile() to see how it treats our operands, and find that the operands don't have the same length
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1:04:45Step through compile() to see how it treats our operands, and find that the operands don't have the same length
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1:09:14Consult the graph of the conditional-sum adder to see a node erroneously containing bit[5]
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1:09:14Consult the graph of the conditional-sum adder to see a node erroneously containing bit[5]
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1:09:14Consult the graph of the conditional-sum adder to see a node erroneously containing bit[5]
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1:09:39Make Example13, the conditional-sum adder, only output the lower bits
1:09:39Make Example13, the conditional-sum adder, only output the lower bits
1:09:39Make Example13, the conditional-sum adder, only output the lower bits
1:10:47Run it to see that we pass the test
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1:10:47Run it to see that we pass the test
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1:10:47Run it to see that we pass the test
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1:11:06Set up to cover carry lookahead adders
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1:11:06Set up to cover carry lookahead adders
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1:11:06Set up to cover carry lookahead adders
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1:11:33Speculative execution in carry lookahead adders
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1:11:33Speculative execution in carry lookahead adders
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1:11:33Speculative execution in carry lookahead adders
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1:13:45Restructuring a ripple-carry adder with indexable bits, towards a carry lookahead adder
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1:13:45Restructuring a ripple-carry adder with indexable bits, towards a carry lookahead adder
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1:13:45Restructuring a ripple-carry adder with indexable bits, towards a carry lookahead adder
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1:19:38Parallelising the carry circuit
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1:19:38Parallelising the carry circuit
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1:19:38Parallelising the carry circuit
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1:29:37Introduce carry_lookahead_adder() and linear_scan()
1:29:37Introduce carry_lookahead_adder() and linear_scan()
1:29:37Introduce carry_lookahead_adder() and linear_scan()
1:33:49Define Example14 as a linear_scan() of XOR
1:33:49Define Example14 as a linear_scan() of XOR
1:33:49Define Example14 as a linear_scan() of XOR
1:34:56Check out the graph of the XOR linear_scan
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1:34:56Check out the graph of the XOR linear_scan
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1:34:56Check out the graph of the XOR linear_scan
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1:35:51Define Example15 as a carry lookahead adder
1:35:51Define Example15 as a carry lookahead adder
1:35:51Define Example15 as a carry lookahead adder
1:36:28Check out the graph of the carry lookahead adder
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1:36:28Check out the graph of the carry lookahead adder
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1:36:28Check out the graph of the carry lookahead adder
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1:36:51Simulate the carry lookahead adder
1:36:51Simulate the carry lookahead adder
1:36:51Simulate the carry lookahead adder
1:37:29Run the carry lookahead adder simulation to find that it doesn't work
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1:37:29Run the carry lookahead adder simulation to find that it doesn't work
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1:37:29Run the carry lookahead adder simulation to find that it doesn't work
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1:38:59Fix pg_compose() to return the operands in the correct order
1:38:59Fix pg_compose() to return the operands in the correct order
1:38:59Fix pg_compose() to return the operands in the correct order
1:40:36Consult the carry lookahead adder graph to determine that it is off-by-one
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1:40:36Consult the carry lookahead adder graph to determine that it is off-by-one
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1:40:36Consult the carry lookahead adder graph to determine that it is off-by-one
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1:41:56Make carry_lookahead_adder() shift the carry right one bit
1:41:56Make carry_lookahead_adder() shift the carry right one bit
1:41:56Make carry_lookahead_adder() shift the carry right one bit
1:44:29rygorous I think you meant c[1:] @ 0
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1:44:29rygorous I think you meant c[1:] @ 0
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1:44:29rygorous I think you meant c[1:] @ 0
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1:44:35Fix carry_lookahead_adder() to slice the carry the correct way
1:44:35Fix carry_lookahead_adder() to slice the carry the correct way
1:44:35Fix carry_lookahead_adder() to slice the carry the correct way
1:44:42Run the carry lookahead adder simulation to find that it passes
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1:44:42Run the carry lookahead adder simulation to find that it passes
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1:44:42Run the carry lookahead adder simulation to find that it passes
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1:45:24Check out the graph of the correct carry lookahead adder
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1:45:24Check out the graph of the correct carry lookahead adder
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1:45:24Check out the graph of the correct carry lookahead adder
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1:46:15Introduce bruteforce_logarithmic_scan()
1:46:15Introduce bruteforce_logarithmic_scan()
1:46:15Introduce bruteforce_logarithmic_scan()
1:47:49Test our bruteforce_logarithmic_scan() and check out the graph
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1:47:49Test our bruteforce_logarithmic_scan() and check out the graph
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1:47:49Test our bruteforce_logarithmic_scan() and check out the graph
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1:48:06Wrap the pg_compose into a PG module
1:48:06Wrap the pg_compose into a PG module
1:48:06Wrap the pg_compose into a PG module
1:49:38Check out the graph of our carry lookahead adder with bruteforce logarithmic scan and PG module
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1:49:38Check out the graph of our carry lookahead adder with bruteforce logarithmic scan and PG module
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1:49:38Check out the graph of our carry lookahead adder with bruteforce logarithmic scan and PG module
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1:50:08Instantiate an 8-bit carry lookahead adder and check out its graph
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1:50:08Instantiate an 8-bit carry lookahead adder and check out its graph
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1:50:08Instantiate an 8-bit carry lookahead adder and check out its graph
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1:51:22Introduce sklansky_scan()
1:51:22Introduce sklansky_scan()
1:51:22Introduce sklansky_scan()
1:54:42Instantiate a 4-bit carry lookahead adder with sklansky_scan and check out its graph
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1:54:42Instantiate a 4-bit carry lookahead adder with sklansky_scan and check out its graph
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1:54:42Instantiate a 4-bit carry lookahead adder with sklansky_scan and check out its graph
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1:55:33Compare bruteforce and Sklansky scan 8-bit carry lookahead adder graphs
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1:55:33Compare bruteforce and Sklansky scan 8-bit carry lookahead adder graphs
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1:55:33Compare bruteforce and Sklansky scan 8-bit carry lookahead adder graphs
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1:56:37spriithy What does the @ operator do?
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1:56:37spriithy What does the @ operator do?
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1:56:37spriithy What does the @ operator do?
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1:57:09Introduce brent_kung_scan() and rename unzip() to interleave()
1:57:09Introduce brent_kung_scan() and rename unzip() to interleave()
1:57:09Introduce brent_kung_scan() and rename unzip() to interleave()
2:04:50Instantiate a 4-bit carry lookahead adder with Brent Kung scan, and check out its graph
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2:04:50Instantiate a 4-bit carry lookahead adder with Brent Kung scan, and check out its graph
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2:04:50Instantiate a 4-bit carry lookahead adder with Brent Kung scan, and check out its graph
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2:08:41That's it for fast adders
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2:08:41That's it for fast adders
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2:08:41That's it for fast adders
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2:10:16Recommend Guy Even's 'On teaching fast adder designs: revisiting Ladner & Fischer'1
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2:10:16Recommend Guy Even's 'On teaching fast adder designs: revisiting Ladner & Fischer'1
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2:10:16Recommend Guy Even's 'On teaching fast adder designs: revisiting Ladner & Fischer'1
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2:11:16That's it for today
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2:11:16That's it for today
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2:11:16That's it for today
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