I seem to remember quite a few recent discussions about pressure sensors on the forum, mostly related to altitude measurement, and would like to know if anyone has interfaced a PICAXE to the SCP1000 device from VTI Technologies. It should be easy to connect directly because there are I2C and SPI versions but I would really appreciate details of interface routines for the PICAXE. Some time ago the Parallax forum had some SPI example code for the Stamp but this information did not show up again when I tried a search.
Smart pressure sensor
- Thread starter MFB
- Start date
Would recommend the i2c version if using the 28X1 or 40X1 as these provide hardware i2c which makes coding much simpler.
SPI can run faster then i2c and is its main advantage but does require more connections. This device is about the the same speed on either bus.
I have had no success with hspi and have not seen any one else report success with hspi on the forum.
There are plenty of examples of i2c code on the forum - searchfor hi2c or i2c*
SPI can run faster then i2c and is its main advantage but does require more connections. This device is about the the same speed on either bus.
I have had no success with hspi and have not seen any one else report success with hspi on the forum.
There are plenty of examples of i2c code on the forum - searchfor hi2c or i2c*
I have managed to find the following Basic Stamp example using SPI, but agree that I2C would be easer with the PICAXE. Maybe SPI is one thing the BS2 does better than the PICAXE?
www.maxentropy.net/stamp/SCP1000/scp1000.htm
www.maxentropy.net/stamp/SCP1000/scp1000.htm
SPI
Hi MFB,
I found this info ages ago when deciding to use Picaxe. Your post has reminded me of it. I'm still learning I2C, don't know about SPI yet, but it seems Peter Anderson has written quite a bit on both barometric pressure and interfacing with SPI. He's talking about different devices (I think) but you may learn something from his web site.
http://www.phanderson.com/picaxe/spi.html
Michael
Hi MFB,
I found this info ages ago when deciding to use Picaxe. Your post has reminded me of it. I'm still learning I2C, don't know about SPI yet, but it seems Peter Anderson has written quite a bit on both barometric pressure and interfacing with SPI. He's talking about different devices (I think) but you may learn something from his web site.
http://www.phanderson.com/picaxe/spi.html
Michael
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The biggest advantage of I2C is that it works ... and if it doesn't, there are far fewer questions to ask to discover why not.
I've nothing against SPI in principle but when it's not working it can be a nightmare to solve and so many variables to consider.
So, I concur with BCJKiwi - Use I2C with a PICAXE for simplicity and fastest route to something working.
I've nothing against SPI in principle but when it's not working it can be a nightmare to solve and so many variables to consider.
So, I concur with BCJKiwi - Use I2C with a PICAXE for simplicity and fastest route to something working.