CAN-View Software Updates

eflier · 02-09-2006, 11:00 PM

Not seeing an updated web-page is usualy your browser set to not check for new page every time; hitting the 'refresh' icon is the quickest fix.

To answer Dolio in this thread now that Evan's set it up, MPG data is not on the CAN or AVC, but the basic elements are: Toyota reports speed in one km per hour increments and fuel burn in ~0.1 litre/hour increments. Any display in other units for different countries is always calculated back to these basics.

So just divide speed by fuel and then convert from km to miles and litres to US gallons. Took me 2 days to remember how to do 16 bit division properly.

I think it's important to realise what these short-lived real high mileage numbers mean, so we don't read too much into them. Yes, I can see 230mpg dawdling along a local flat road. And yes it helps to increase the overall real mileage. But you should realise what the numbers are based on before we get a bunch of ' I got 235mpg and you only saw 227mpg' posts.

mpg is speed (miles per hour) divided by fuel burn rate (gallon sper hour)
So as the fuel burn rate gets progressively smaller for these very high mpg figures, the resolution of the result begins to suffer. For example, suppose at 35mph by some means you manage to burn just 0.15 usg/hour, resulting in 233 mpg. The smallest possible change to this is the 0.1 litre (or 0.0268 usgallon) increment reported by CAN, so that changes the answer to 35/(0.15+0.0268) =198mpg Its not that it suddenly dropped from 233 mpg to 198mpg, its that the Prius only reported the fuel flow change to that resolution. In contrast, at normal rates of say 60mph and 1.2usg/hr for 50mpg, each increment is only2% and so not so obvious. Any attempt to filter these results in software is just making a pretty display, its not showing the real result.

I knew this would then lead to someone saying, well why can't also we have average mpg over a longer time or distance? This is much more complicated because it means keeping track of all speed and fuel data constantly and with all the housekeeping tasks CANview has to do this is not a simple matter. I suspect the Prius manages average mpg because it has a much more powerful processor and very little else to do. I am trying something similar with Amp-hours and by not collecting every single message while I handle other things, I build up a significant cumulative error. It needs a new approach to recognise vital messages and process every one, but recognise relatively unimportant repeat messages ando do the necessary chores during them. It can probably be done, but don't expect it too soon.

**efusco** · 02-10-2006, 09:35 PM

The current version is a nice update Norm. If it's not a big problem I'd suggest putting an "infinity" symbol or a C (for coast) or an S (for stealth), or N/A or div/0 or just some --- instead of just the blank space...it's kinda odd when the readout area goes completely away.

joelparks · 02-10-2006, 10:02 PM

Quote:

Originally posted by eflier@Feb 9 2006, 05:40 PM
Feb 9th: latest Beta test codes posted for those who like to take their CAN-videws indoors and talk to them. Adds instantaneous MPG in text, format and graph form.
Thats miles-per-US-gallon for now till I get more feedback. For simplicity I've limited maximum displayed MPG to 255. I also think the occasions its over 100mpg are so rare that the graph would be more use if it were scaled 0-100 (but leave the numbers still displaying to 255) I can change it. But no doubt I'll hear other ideas.....

Seeing 3mpg as I scoot off from an intersection is scary enough.

Load all 3 codes or you won't get the right text on the format screen from the TV chip and you won't get a fix for occasional low temperature start problems in the IE chip.

[snapback]206642[/snapback]

I just want to take this opportunity to point out how fortunate we are to have Norm working on this nifty widget. While I'm feeling a little deprived that I haven't had a chance to connect with my neighbor tomdeimos and update to newer (or newest) code yet, and a little guilty that I'm not really contributing to the 'effort' (I try not to drive around too much,) I'm still sort of amazed (and definitely thrilled) that Norm is popping out these updates like this.

Thanks again Norm!
Joel

arniesalsared · 02-10-2006, 10:18 PM

What would we do without Norm??

If I was an avid Republican I's say "MegaDittos"! But I'm not too avid anymore.
Arnie

DaveinOlyWA · 02-10-2006, 11:38 PM

any thoughts on the mystery graph?? it seems to only run when the ICE does. i rotated each graph option with the mystery to see if any seemed to match. although it doesnt vary in any discernable ratio with ICE RPM, it does come on at the same time the ICE does.

eflier · 02-11-2006, 01:45 PM

Evan suggests that instead of X2 size display going blank at 255 mpg, it be infinity or at least '---' My limited X2 char set means I can't offer the logical infinity sign, but I can put in '!!!!' or '****' or '----'
preferences?
hmmm, space for 4 letters possible... if you drive really carefully, your mpg can get to 'evan'? sorry, bad pun, couldn't resist.

Also as the amount of time >100mpg is very limited, should I scale the graph portion alone to be say 100mpg =full scale bar, (but leaving the numbers to go to 255) so its more useful in 'normal' driving
Preferences?

tomdeimos · 02-11-2006, 01:53 PM

I vote for doing similar to Toyota!

For graph: go to 100 and when higher just read 100.

For text: go to 255 and when over just read 255.

DaveinOlyWA · 02-11-2006, 02:14 PM

how about ∑...

! to me means an error (which in this case maybe true)

? means unknown (the rate could be figured if we determined how much gas it takes to burn to get a certain amount of charge and factored in how fast we were dissipating the charge

or we could use Џ to symbolize a goal or "touchdown" metaphorically.

or maybe

Ө to symbolize hybriditiy... half gas half electric...since the electricity came from the gas...

or maybe ♫ to symbolize "humming along in EV?"

or maybe...ok maybe im getting carried away by the character map. you say you can do 4 characters??? how about 9999?

Frank Hudon · 02-11-2006, 02:14 PM

include my vote for "evan"

Frank Hudon · 02-11-2006, 04:07 PM

Quote:

Originally posted by DaveinOlyWA@Feb 11 2006, 11:14 AM
how about 9999?

[snapback]207730[/snapback]

boy your going to do a double take when it goes from 9999 down to 198, I'll probably hear you scream all the way up here.

02-11-2006, 02:14 PM	#18
DaveinOlyWA 3rd Time was Solariffic!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 12,382 My Car: 2010 Prius Model: IV Package: Solar Roof Thanks: 24 Thanked 122 Times in 104 Posts Friends: 10	how about ∑... ! to me means an error (which in this case maybe true) ? means unknown (the rate could be figured if we determined how much gas it takes to burn to get a certain amount of charge and factored in how fast we were dissipating the charge or we could use Џ to symbolize a goal or "touchdown" metaphorically. or maybe Ө to symbolize hybriditiy... half gas half electric...since the electricity came from the gas... or maybe ♫ to symbolize "humming along in EV?" or maybe...ok maybe im getting carried away by the character map. you say you can do 4 characters??? how about 9999? __________________ My Blue 2010 : Last tank 541.9 @ 49.48 pump (56.7 MFD) 5.54 CPM, 21 MPH, Lifetime:5442.2 miles 56.5 MPG pump. (62.22 MFD) 4.72 CPM. Summer MPG 57.4 Winter: 49.5 My 2006 SPM: Last tank 376.6 miles @38.21 pump (40.8 MFD) 7.17 cpm winter mpg 49.64 summer mpg 53.41 lifetime: 42,563.5 miles 51.5 mpg pump (52.7 mpg MFD) 5.51 cpm My 2007 Zenn total "fuel cost" $166.58 on "about" 9599.7 miles. 1.74 cents per mile (granted i plug in for free at work!!) My Plate: DUALPWR (Dual Power)

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Any Prius software updates or hacks?	BoHenriksson	Gen II Prius Technical Discussion	5	08-30-2007 09:35 PM
Can View from a Tech's point of view	IFixEm	Gen II Prius Audio and Electronics	4	01-28-2006 12:14 PM
US Updates UPS Signal	pjm877	Gen II Prius Main Forum	1	01-26-2006 10:43 AM
Navigation updates	mhartley	Gen II Prius Audio and Electronics	19	12-01-2005 09:23 AM
DVD Navigation updates	SDiego	Gen II Prius Care, Maintenance and Troubleshooting	23	07-12-2005 10:23 AM

02-09-2006, 11:00 PM	#11
eflier Silver Business Sponsor Join Date: Jul 2005 Location: Fraser Valley BC Posts: 164 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Not seeing an updated web-page is usualy your browser set to not check for new page every time; hitting the 'refresh' icon is the quickest fix. To answer Dolio in this thread now that Evan's set it up, MPG data is not on the CAN or AVC, but the basic elements are: Toyota reports speed in one km per hour increments and fuel burn in ~0.1 litre/hour increments. Any display in other units for different countries is always calculated back to these basics. So just divide speed by fuel and then convert from km to miles and litres to US gallons. Took me 2 days to remember how to do 16 bit division properly. I think it's important to realise what these short-lived real high mileage numbers mean, so we don't read too much into them. Yes, I can see 230mpg dawdling along a local flat road. And yes it helps to increase the overall real mileage. But you should realise what the numbers are based on before we get a bunch of ' I got 235mpg and you only saw 227mpg' posts. mpg is speed (miles per hour) divided by fuel burn rate (gallon sper hour) So as the fuel burn rate gets progressively smaller for these very high mpg figures, the resolution of the result begins to suffer. For example, suppose at 35mph by some means you manage to burn just 0.15 usg/hour, resulting in 233 mpg. The smallest possible change to this is the 0.1 litre (or 0.0268 usgallon) increment reported by CAN, so that changes the answer to 35/(0.15+0.0268) =198mpg Its not that it suddenly dropped from 233 mpg to 198mpg, its that the Prius only reported the fuel flow change to that resolution. In contrast, at normal rates of say 60mph and 1.2usg/hr for 50mpg, each increment is only2% and so not so obvious. Any attempt to filter these results in software is just making a pretty display, its not showing the real result. I knew this would then lead to someone saying, well why can't also we have average mpg over a longer time or distance? This is much more complicated because it means keeping track of all speed and fuel data constantly and with all the housekeeping tasks CANview has to do this is not a simple matter. I suspect the Prius manages average mpg because it has a much more powerful processor and very little else to do. I am trying something similar with Amp-hours and by not collecting every single message while I handle other things, I build up a significant cumulative error. It needs a new approach to recognise vital messages and process every one, but recognise relatively unimportant repeat messages ando do the necessary chores during them. It can probably be done, but don't expect it too soon.

02-10-2006, 09:35 PM	#12
efusco Troll Slayer Join Date: Nov 2003 Location: Nixa, MO Posts: 17,255 My Car: 2004 Prius Model: Package: #9 Thanks: 50 Thanked 262 Times in 157 Posts Friends: 37	The current version is a nice update Norm. If it's not a big problem I'd suggest putting an "infinity" symbol or a C (for coast) or an S (for stealth), or N/A or div/0 or just some --- instead of just the blank space...it's kinda odd when the readout area goes completely away.

02-10-2006, 10:18 PM	#14
arniesalsared Member Join Date: Aug 2004 Location: Phoenix, AZ Posts: 39 My Car: 2004 Prius Model: Package: #8 Thanks: 0 Thanked 1 Time in 1 Post Friends: 0	What would we do without Norm?? If I was an avid Republican I's say "MegaDittos"! But I'm not too avid anymore. Arnie

02-10-2006, 11:38 PM	#15
DaveinOlyWA 3rd Time was Solariffic!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 12,382 My Car: 2010 Prius Model: IV Package: Solar Roof Thanks: 24 Thanked 122 Times in 104 Posts Friends: 10	any thoughts on the mystery graph?? it seems to only run when the ICE does. i rotated each graph option with the mystery to see if any seemed to match. although it doesnt vary in any discernable ratio with ICE RPM, it does come on at the same time the ICE does.

02-11-2006, 01:45 PM	#16
eflier Silver Business Sponsor Join Date: Jul 2005 Location: Fraser Valley BC Posts: 164 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Evan suggests that instead of X2 size display going blank at 255 mpg, it be infinity or at least '---' My limited X2 char set means I can't offer the logical infinity sign, but I can put in '!!!!' or '****' or '----' preferences? hmmm, space for 4 letters possible... if you drive really carefully, your mpg can get to 'evan'? sorry, bad pun, couldn't resist. Also as the amount of time >100mpg is very limited, should I scale the graph portion alone to be say 100mpg =full scale bar, (but leaving the numbers to go to 255) so its more useful in 'normal' driving Preferences?

02-11-2006, 01:53 PM	#17
tomdeimos Join Date: Feb 2004 Location: Lexington, MA Posts: 995 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	I vote for doing similar to Toyota! For graph: go to 100 and when higher just read 100. For text: go to 255 and when over just read 255.

02-11-2006, 02:14 PM	#19
Frank Hudon Senior Member Join Date: Jan 2004 Posts: 4,144 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	include my vote for "evan"