speedometer help
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Can someone please help me make a program for a dig. dash?
The only help that i need is for a BS2 to learn on the fly. the
sender works by putting out a few pulses per rev of the cable. The
way i want the stamp to work is: when i get to 60mph i push a button
the stamp will read how meny pulses there are at 60mph.
example: 30000 = 60mph.
then it will store it in the eeprom. but the pulses are only a
varable they go up and down with the speed.
example: 29500 pulses = 59mph
29000 pulses = 58mph
28500 pulses = 57mph
I heve seen after market speedometers that can take a 500 to 20000
pules per mile (not mile per hour)
please help me.
TC
The only help that i need is for a BS2 to learn on the fly. the
sender works by putting out a few pulses per rev of the cable. The
way i want the stamp to work is: when i get to 60mph i push a button
the stamp will read how meny pulses there are at 60mph.
example: 30000 = 60mph.
then it will store it in the eeprom. but the pulses are only a
varable they go up and down with the speed.
example: 29500 pulses = 59mph
29000 pulses = 58mph
28500 pulses = 57mph
I heve seen after market speedometers that can take a 500 to 20000
pules per mile (not mile per hour)
please help me.
TC
Comments
pulses so make the count time a variable and use a pushbutton to change the
count time.
aconti@n... wrote:
>
> Can someone please help me make a program for a dig. dash?
>
> The only help that i need is for a BS2 to learn on the fly. the
> sender works by putting out a few pulses per rev of the cable. The
> way i want the stamp to work is: when i get to 60mph i push a button
> the stamp will read how meny pulses there are at 60mph.
>
> example: 30000 = 60mph.
>
> then it will store it in the eeprom. but the pulses are only a
> varable they go up and down with the speed.
>
> example: 29500 pulses = 59mph
> 29000 pulses = 58mph
> 28500 pulses = 57mph
>
> I heve seen after market speedometers that can take a 500 to 20000
> pules per mile (not mile per hour)
> please help me.
>
> TC
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
I got my stamp in Jan and my first real project was to use the BS2
and a PocketPC for acquisition of RPM's. Works like a charm and
pretty simple to do. Use the count function and the serout function
of the BS2 and the comm control of the PocketPC to read the output
from the stamp. Other telemetry of the car can be acquired this way
and the data can then be used in an engine analysis program like a
dynamometer.
Just be sure to connect the output pin from the stamp to the input
pin of the PPC, it works better that way, Heheh. Also someone
suggested a 220k resister on the data line. I'm not sure what it's
for but I imagine it's to keep things from getting to hot. I can use
the PPC to keep my coffee warm when not reading RPM's [noparse]:o[/noparse]
For even more fun you can e-mail the manufacture of the PPC and tell
them of your hardware application and they'll wooo you with all sorts
of really neat stuff for free.
1. 30000 pulses per mile
2. @ 60 mph = 1 mile per minute
3. 1 mile per minute = 30000 / 60 or 500 pulses per second
4. Now if you use the count command for 500 mS you would get a reading of
60 @ 30000 pulses per mile
at 29500 pulses per mile using the count command for 500 mS you would get a
reading of 59 so you can see that changing the count command timing would
do the trick, the only problem with the stamp is it has no timer, so you
cannot start the counting and a timer at the same time or (real close to
the same time) to count to 60 and get a timer value, which you would use
this value for the count command time. A pic could do this using internal
timer. You can still use this Idea but you will need two pushbuttons one
for up and one for down if you are going 60 mph you push a button up or
down which changes the count command's time and you will see the speed
going up or down, once set this value can be stored into eeprom and upon
startup read this value first, then the count command will use this value
for its time base there are other ways for doing this I measure tire size
and and calculate the pulses this way using PI and make it set-able without
driving with someone else telling me im going 60 mph and pushing buttons (
Will you be talking on the Cell phone while doing this ).
good luck
larry gaminde
aconti@n... wrote:
>
> Can someone please help me make a program for a dig. dash?
>
> The only help that i need is for a BS2 to learn on the fly. the
> sender works by putting out a few pulses per rev of the cable. The
> way i want the stamp to work is: when i get to 60mph i push a button
> the stamp will read how meny pulses there are at 60mph.
>
> example: 30000 = 60mph.
>
> then it will store it in the eeprom. but the pulses are only a
> varable they go up and down with the speed.
>
> example: 29500 pulses = 59mph
> 29000 pulses = 58mph
> 28500 pulses = 57mph
>
> I heve seen after market speedometers that can take a 500 to 20000
> pules per mile (not mile per hour)
> please help me.
>
> TC
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/