pass spi object

slcott

I'm still learning how to use the propeller. The propeller on my board is trying to communicate over SPI to multiple chips. I'd like to use an SPI object in each of the spin files that I have associated with each of the IC's that the microprocessor communicates with.

• Some of my objects
  DAC : "digital analog converter"
  ADC : "analog digital converter"
  FPU : "floating point unit"
  SPI : "spi asm"

It seems that only one of my objects can allocate the SPI object at a time. Can I pass this object around or should I just implement the SPI interface within each of the different objects that I am working with.

MagIO2

You need an obj section in each of the objects that want to use SPI which defines it's own instance of SPI. But be aware that some objects might be designed as a singleton. This means that only one instance is allowed. This is the case when the object has DAT variables. (DAT constants -for example strings- are OK).

Of course the different SPI objects should all work on different PINs if they run in different COGs. Otherwise, if you run the different SPI instances in different COGs AND you want to use the same SPI bus, you have to add code to synchronize the access.