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The Power of a Look-up Table

Nathan Jones - Watch Now - EOC 2024 - Duration: 52:55

The Power of a Look-up Table
Nathan Jones

Look-up tables have been speeding up math operations for time immemorial, but there's more to this simple programming "idiom" than just numbers in an array. Join me in this talk as we discover and categorize the different ways we can store and retrieve data from arrays in ways that enable all sorts of fun and useful things, from creating digital music to building jump tables that drive command parsers or finite state machines.

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Score: 0 | 1 week ago | no reply

An excellent presentation on an often overlooked aspect of embedded systems design.

Score: 0 | 3 weeks ago | no reply

A great talk on a subject not talked about enough - and thank you for your service, Nathan.

Score: 0 | 2 months ago | no reply

Good talk. I think you meant 0.5mm accuracy, not 0.5cm at 03:30 in? The library function performance depends on if you have a double or single precision MMU. One major advantage of tables is ensuring all cases/states are covered, easily missed in complex nested if else statements. I’ve used a variation of memoisation, where the tables are.stored in RAM and fully computed once during initialisation when there’s time to do so. I’ve found a good use for them in generic UART configuration and handlers. There are examples of table-based initialisation of tasks in Jacob’s book. I partcularly liked your button metadata and CLI parser.

Score: 0 | 2 months ago | no reply

Thank you very much Nathan, I am always looking forward to your talks in the conference. I really appreciate your thorough investigation and great delivery. Thanks for the book recommendation.

Score: 1 | 2 months ago | no reply

Thanks for that thorough presentation on lookup tables. I think you touched on every way I have used lookup tables over the years and more.. A classic use case is for really fast CRC generation. Thanks for providing the links. Good stuff.

Score: 1 | 2 months ago | no reply

Great talk, Nathan! I loved how you applied LUTs in different practical applications and also provided additional links for reading. Thank you so much. I sometimes forget how invaluable and expandable LUTs are.

Score: 0 | 2 months ago | no reply

Slides are now posted. Sorry about the delay, folks!