private bool EndTransaction(Configuration configuration)
{
SpiDevice spiDevice = this.Emulator.SpiBus.GetActiveDevice();
if (configuration.ChipSelect_Port != Cpu.Pin.GPIO_NONE)
{
this.Emulator.ManagedHal.Gpio.SetPinState((uint)configuration.ChipSelect_Port, !configuration.ChipSelect_ActiveState);
}
if (!IsInTransaction)
{
Debug.Assert(false, "not in a SPI transaction");
Trace.WriteLine("Error: Attempt to end a transaction when none is in place.");
return(false);
}
if (_spiDeviceCurrent != spiDevice)
{
Debug.Assert(false, "wrong SPI device");
Trace.WriteLine("Error: Attempt to end a transaction, but the SPI device does not match.");
return(false);
}
_spiDeviceCurrent = null;
return(true);
}
private void SetConfiguration(Configuration configuration)
{
_chipSelectPin = configuration.ChipSelect_Port;
_chipSelectActiveState = configuration.ChipSelect_ActiveState;
_chipSelectSetupTime = configuration.ChipSelect_SetupTime;
_chipSelectHoldTime = configuration.ChipSelect_HoldTime;
_clockIdleState = configuration.Clock_IdleState;
_clockEdge = configuration.Clock_Edge;
_clockRateKHz = configuration.Clock_RateKHz;
_spiModule = configuration.SpiModule;
}
private Configuration SpiConfigurationToConfiguration(SpiConfiguration configuration)
{
Configuration cfg = new Configuration(
(Cpu.Pin)configuration.DeviceCS,
configuration.CS_Active,
configuration.CS_Setup_uSecs,
configuration.CS_Hold_uSecs,
configuration.MSK_IDLE,
configuration.MSK_SampleEdge,
configuration.Clock_RateKHz,
(Hardware.Spi.SpiModule)configuration.SPI_mod);
return(cfg);
}
private bool StartTransaction(Configuration configuration)
{
if (IsInTransaction)
{
Debug.Assert(false, "already in a SPI transaction");
Trace.WriteLine("Error: Attempt to start a transaction when another one is in place.");
return(false);
}
if (configuration.ChipSelect_Port != Cpu.Pin.GPIO_NONE)
{
this.Emulator.ManagedHal.Gpio.SetPinState((uint)configuration.ChipSelect_Port, configuration.ChipSelect_ActiveState);
}
_spiDeviceCurrent = this.Emulator.SpiBus.GetActiveDevice();
return(true);
}
bool ISpiDriver.nWrite8_nRead8(ref SpiConfiguration Configuration, IntPtr Write8, int WriteCount, IntPtr Read8, int ReadCount, int ReadStartOffset)
{
Configuration configuration = SpiConfigurationToConfiguration(Configuration);
bool res = false;
try
{
if (StartTransaction(configuration))
{
SpiXaction xaction = new SpiXaction(Write8, WriteCount, Read8, ReadCount, ReadStartOffset);
res = ((ISpiDriver)this).Xaction_nWrite8_nRead8(ref xaction);
}
}
finally
{
res &= EndTransaction(configuration);
}
return(res);
}
public SpiDevice(Configuration configuation)
{
SetConfiguration(configuation);
}
bool ISpiDriver.Xaction_Stop(ref SpiConfiguration Configuration)
{
Configuration configuration = SpiConfigurationToConfiguration(Configuration);
return(EndTransaction(configuration));
}