RE: RE: STREP FP6 proposal

["Ruth Ivimey-Cook" <Ruth.Ivimey-Cook@xxxxxxxxxx>]

Stepehn,

 

The Evo case seems more to be a case of the absence of proper power management. There should have been a controller whose job it is to manage the power budget and ensure that essential services (itself, traction control, injection control, etc) are given priority over non-essential services (hifi, aircon, electric windows). Even a basic PIC could do that job! 

 

And one might be able improve the parked case: why have half a dozen systems powered up so that the keylock and alarm can function? ... or does an alarm system take a good deal more than a few tens of milliamps to operate by itself. ....fx: search google... that said, in a 15 minute search I didn't find any car alarm specs that even mentioned a power budget. I guess that speaks for itself.

 

Regards,

 

Ruth

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From: Stephen Maudsley [mailto:sjmaudsley@xxxxxxxxxxxxxxxxxxxxxx]
Sent: Thursday, May 12, 2005 10:07 AM
To: Ruth Ivimey-Cook; eric.verhulst@xxxxxxxxxxxxxxxxxxxxxx; Ruth.Ivimey-Cook@xxxxxxxxxx; occam-com@xxxxxxxxxx
Subject: Re: RE: STREP FP6 proposal

> supplies to automotive and in this market high reliability,
> low cost and low power are severe boundary conditions ).

I can readily understand low cost and high reliability, but why is low power,
when you've large numbers of amps being generated in the next compartment?

Ruth

Whilst that is true, when you run out of amps the effects can be catastrophic. I recall the case of the Evo where the driver turned on the hifi, the voltage rails dropped, the traction control failed and it wrapped around a lamp post on the next bend. That may have been a case of successfull Darwinism but with 30+ computers then there is more of an effect to take into account.

I suspect that as we attempt to use the technology for lower power cars (look at the price of fuel...) that the power budget is more of an issue.