the bosch BMP085
http://parts.digikey.com/1/parts/163094 … mp085.html
pressure sensor is very accurate and digital. and small.
gives competition for the SCP1000 at a fraction of the price.
says less than 0.25m accuracy with some added filtering…
10 bux per chip at digikey in low volume.
sparkfun how about a breakout board?
Not quite the same, it’s actually not that accurate when compared to the SCP1000.
250 Pa
and noise is umm like 3 Pa
yah its not as accurate.
but for the price ???
For the price yes it is decent.
In fact I have a breakout board I designed up a few months ago for it, I just haven’t got around to getting a sensor and testing it.
hey send it over to sparkfun, maybe theyll sell em for you…
id buy one… just to test em out./
if u buy em in bulk its 4 bux per chip.
= 5 or 6 bux.
for the performance, and price point… just cant pass this one up.
just need something cheaper than the SCP1000 and freescales (and others) solutions are just not accurate enough.
what would really be nice is if they put a plastic port on the SCP1000 hahahaha…
that would be nice.
I add my vote for a breakout board with the Bosch BMP085.
The stated absolute accuracy of the Bosch chip (+/- 250 Pa) and rms noise (3 Pa) is only a factor of 2 worse than the much more expensive SCP1000. A little averaging goes a long way!
Sparkfun, how about it?
I have just finished writing a driver for the BMP085, hope to test it next week.
I know someone was getting 50cm altitude resolution on the lowest resolution setting. So I am keen to test if out.
One thing I don’t like about the BMP085 is the way it does the conversions. I would like to be able to set it in a continuous free-running mode where it keeps taking measurements itself and then you can just poll the sensor to get the latest value.
You might be able to do this, but so far the datasheet hasn’t said anything about it.
The way I have written the driver it at the moment is like the datasheet, but instread of waiting for ‘x’ seconds I use the end of conversion (EOC) interrupt. The process is:
Send StartTempADC Command
Interrupt on EOC
Read ADC Result, Store
Send StartPressureADC Command
Interrupt on EOC
Read ADC Result, Store
If anyone knows if I can set the sensor in a continuous mode I would really like to know.