I have not heard of anyone needing more than one accelerometer, but I am assuming you are talking about a standard 3-axis chip.
If you want to use more than one 3-axis chip, then I am very curious about your application/idea.
Conceptually, all you need is enough A/D ports on your PSOC to do the basic interface. As I recall, there are at least twelve on the board, so you should be able to make it work.
The MMA7455L has both I2C and SPI outputs. I would recommend using SPI. Connect MISO, MOSI and CLK lines together. Then use two different select signals, and control them manually (via a control register) in your code. With that setup, you can use a single SPI master component, and select manually which one to talk to.
in this design I connected 7 gyro's and 7 accelerometers to one microcontroller:)
I used SPI for that, with chip selects.
The reason for choosing SPI was that we needed to get the data within a certain time after a synchronisation trigger, and SPI is much faster than I2C. The MMA455L has an address pin, so you could easily connect two of these to one I2C bus.
I have to admit, this is an area that I only spent a limited time working on projects. So in my mind, one accelerometer was plenty, but now I can see a much larger world where they could be employed. Its always a good day to learn something new.
Since SPI is a bus, there is no need to use multiple masters. Multiple chip-select signals are enough (and save pins that way). Different masters are only needed when the SPI configuration (CPOL / CPHA) are needed.
Thank you for your answer. In this case, I want to show in PC about 8 direction movement (like direction of the wind, e.g: N, NE, E, SE, S, SW, W, NW) using two accelerometer
I can't see why you'd need two accelerometers for that... Please look into 2- or 3-axis accelerometers, they can give you 2-axis information in a single package!
