2 replies to this topic

[Squintz]

What about the following code is causing an exception to be thrown when I create a new SPI object? The exception says

#### Exception System.Exception - CLR_E_PIN_UNAVAILABLE (2) ####
#### Message:
#### Microsoft.SPOT.Hardware.Port::.ctor [IP: 0000] ####
#### Microsoft.SPOT.Hardware.OutputPort::.ctor [IP: 0006] ####
#### Microsoft.SPOT.Hardware.SPI::.ctor [IP: 004d] ####
#### NetduinoApplication1.Program::.cctor [IP: 0024] ####
A first chance exception of type 'System.Exception' occurred in Microsoft.SPOT.Hardware.dll
An unhandled exception of type 'System.Exception' occurred in Microsoft.SPOT.Hardware.dll

Uncaught exception
The thread '<No Name>' (0x2) has exited with code 0 (0x0).
#### Exception System.NullReferenceException - CLR_E_NULL_REFERENCE (1) ####
#### Message:
#### NetduinoApplication1.Program::Main [IP: 000b] ####
A first chance exception of type 'System.NullReferenceException' occurred in NetduinoApplication1.exe
An unhandled exception of type 'System.NullReferenceException' occurred in NetduinoApplication1.exe

        public static SPI.Configuration spi_config = new SPI.Configuration(Pins.GPIO_PIN_D13,
                                      false,
                                      1,
                                      1,
                                      true,
                                      false,
                                      15000,
                                      SPI_Devices.SPI1);

        public static SPI mySPI = new SPI(spi_config);

[Chris Walker]

Hi Squintz, At first glance...Pins.GPIO_PIN_D13 is the clock line for the SPI...you won't be able to use that as your Chip Select line. I would recommend Pins.GPIO_PIN_D10 in most cases... The following three pins are not available when using SPI (since they are the SPI data lines): Pins.GPIO_PIN_D11 (SPI Slave Input) Pins.GPIO_PIN_D12 (SPI Slave Output) Pins.GPIO_PIN_D13 (SPI Clock) Chris

[Squintz]

Doh! I traced the wrong wire out.