Comments on: Engine Control Units (ECUs) http://twoguysrally.com/2008/06/11/engine-control-units-ecus/ Two guys on a journey into the Rally Racing world Wed, 07 Jan 2009 01:29:00 +0000 http://wordpress.org/?v=2.5 By: Charles Smith http://twoguysrally.com/2008/06/11/engine-control-units-ecus/#comment-500 Charles Smith Wed, 13 Aug 2008 06:21:34 +0000 http://twoguysrally.com/?p=69#comment-500 Yes sir it is. It is much cheaper and easier to use the memory in place of a 'Real Time' unit. The more flexible ECUs are there. Mega/Microsquirts is an opensource version that does a bit of neat stuff. Autronic, GReddy, etc... are all adding to the wonderful world of ECUs. Yes sir it is. It is much cheaper and easier to use the memory in place of a ‘Real Time’ unit.

The more flexible ECUs are there. Mega/Microsquirts is an opensource version that does a bit of neat stuff. Autronic, GReddy, etc… are all adding to the wonderful world of ECUs.

]]> By: Jon http://twoguysrally.com/2008/06/11/engine-control-units-ecus/#comment-499 Jon Wed, 13 Aug 2008 05:21:51 +0000 http://twoguysrally.com/?p=69#comment-499 This concept is called Space-time trade off and it is a fundamental concept of computer science. The idea of using a lookup table in an ECU biases to using more space(computer memory) that cpu time. That means use more space and save more time. These tables are generated using simple formulas so theoretically the ECU is capable of calculating the values on the fly but that takes more time (which means faster, more expensive processors to keep up with the engine.) With the cost of memory continuing to fall, it is much more effective to pre-generate massive tables (By massive I mean a few megabytes) for every conceivable condition and store them on large chips rather than trying to put expensive heat, power, and cash consuming processors in modern ECUs. However I can imagine there is a market for a more flexible ECU, maybe for after market application that can accommodate additional tasks like boost, vvt, and other technologies that require computation. Something like this would require a powerful processor because it can't anticipate what devices that it will be controlling. This concept is called Space-time trade off and it is a fundamental concept of computer science. The idea of using a lookup table in an ECU biases to using more space(computer memory) that cpu time. That means use more space and save more time. These tables are generated using simple formulas so theoretically the ECU is capable of calculating the values on the fly but that takes more time (which means faster, more expensive processors to keep up with the engine.) With the cost of memory continuing to fall, it is much more effective to pre-generate massive tables (By massive I mean a few megabytes) for every conceivable condition and store them on large chips rather than trying to put expensive heat, power, and cash consuming processors in modern ECUs.
However I can imagine there is a market for a more flexible ECU, maybe for after market application that can accommodate additional tasks like boost, vvt, and other technologies that require computation. Something like this would require a powerful processor because it can’t anticipate what devices that it will be controlling.

]]> By: Charles Smith http://twoguysrally.com/2008/06/11/engine-control-units-ecus/#comment-315 Charles Smith Sun, 06 Jul 2008 23:30:45 +0000 http://twoguysrally.com/?p=69#comment-315 Unfortunately I forgot to mention a critical sensor. the Cam sensor. Otherwise how would it know when to inject fuel :( Unfortunately I forgot to mention a critical sensor. the Cam sensor. Otherwise how would it know when to inject fuel :(

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