public Task Send(uint address, byte[] data)
{
Contract.Requires(data, "data")
.NotToBeNull();
return(Task.Run(() =>
{
uint transferredSize;
var status = NativeMethods_I2C.I2C_DeviceWrite(
this.ChannelHandle,
address,
(uint)data.Length,
data,
out transferredSize,
WriteOptions |
NativeMethods_I2C.TransferOptions.I2C_TRANSFER_OPTIONS_START_BIT |
NativeMethods_I2C.TransferOptions.I2C_TRANSFER_OPTIONS_STOP_BIT);
if (status != FTDI.FT_STATUS.FT_OK || transferredSize != data.Length)
{
throw new CommunicationException("Error while writing to the bus. (Status: " + status + ")");
}
}));
}
public Task <byte[]> Transceive(uint address, byte[] dataToSend, int receiveLength)
{
Contract.Requires(dataToSend, "dataToSend").NotToBeNull();
Contract.Requires(receiveLength, "receiveLength").ToBeInRange(x => x > 0);
return(Task.Run(() =>
{
uint transferredSize;
// Send data
var status = NativeMethods_I2C.I2C_DeviceWrite(
this.ChannelHandle,
address,
(uint)dataToSend.Length,
dataToSend,
out transferredSize,
WriteOptions | NativeMethods_I2C.TransferOptions.I2C_TRANSFER_OPTIONS_START_BIT);
if (status != FTDI.FT_STATUS.FT_OK || transferredSize != dataToSend.Length)
{
throw new CommunicationException("Error while writing to the bus. (Status: " + status + ")");
}
// Receive data
var buffer = new byte[receiveLength];
status = NativeMethods_I2C.I2C_DeviceRead(
this.ChannelHandle,
address,
(uint)receiveLength,
buffer,
out transferredSize,
ReadOptions |
NativeMethods_I2C.TransferOptions.I2C_TRANSFER_OPTIONS_START_BIT |
NativeMethods_I2C.TransferOptions.I2C_TRANSFER_OPTIONS_STOP_BIT |
NativeMethods_I2C.TransferOptions.I2C_TRANSFER_OPTIONS_NACK_LAST_BYTE);
if (status != FTDI.FT_STATUS.FT_OK)
{
throw new CommunicationException("Error while reading from the bus. (Status: " + status + ")");
}
if (transferredSize < receiveLength)
{
// If less bytes receive as expected => Copy to smaller array
var tmpData = new byte[transferredSize];
Array.Copy(buffer, tmpData, transferredSize);
buffer = tmpData;
}
return buffer;
}));
}
/// <summary>
/// Disconnects from device.
/// </summary>
public Task Disconnect()
{
if (this.ChannelHandle == IntPtr.Zero)
{
return(Task.CompletedTask);
}
// Close the channel
return(Task.Run(() =>
{
var status = NativeMethods_I2C.I2C_CloseChannel(this.ChannelHandle);
this.DeviceNode = null;
this.ChannelHandle = IntPtr.Zero;
if (status != FTDI.FT_STATUS.FT_OK)
{
throw new CommunicationException("Unable to close I2C channel. (Status: " + status + ")");
}
}));
}
public Task <byte[]> Receive(uint address, int dataLength)
{
Contract.Requires(dataLength, "dataLength")
.ToBeInRange(x => x > 0);
return(Task.Run(() =>
{
var buffer = new byte[dataLength];
uint transferredSize;
var status = NativeMethods_I2C.I2C_DeviceRead(
this.ChannelHandle,
address,
(uint)dataLength,
buffer,
out transferredSize,
ReadOptions |
NativeMethods_I2C.TransferOptions.I2C_TRANSFER_OPTIONS_START_BIT |
NativeMethods_I2C.TransferOptions.I2C_TRANSFER_OPTIONS_STOP_BIT);
if (status != FTDI.FT_STATUS.FT_OK)
{
throw new CommunicationException("Error while reading from the bus. (Status: " + status + ")");
}
if (transferredSize < dataLength)
{
// If less bytes receive as expected => Copy to smaller array
var tmpData = new byte[transferredSize];
Array.Copy(buffer, tmpData, transferredSize);
buffer = tmpData;
}
return buffer;
}));
}
/// <summary>
/// Connects to the FTDI device.
/// </summary>
/// <param name="serialNumber">A FTDI device serial number.</param>
/// <param name="deviceChannelIndex">A channel index in the device.</param>
public virtual Task Connect(string serialNumber, int deviceChannelIndex)
{
return(Task.Run(() =>
{
FTDI.FT_STATUS status;
NativeMethods.Init_libMPSSE();
// Find requested channel
uint channelCount;
status = NativeMethods_I2C.I2C_GetNumChannels(out channelCount);
if (status != FTDI.FT_STATUS.FT_OK)
{
throw new CommunicationException("Unable to find number of I2C channels. (Status: " + status + ")");
}
uint channelIndex;
var deviceNode = new NativeMethods.FT_DEVICE_LIST_INFO_NODE();
var tmpChannelIndex = deviceChannelIndex;
for (channelIndex = 0; channelIndex < channelCount; channelIndex++)
{
status = NativeMethods_I2C.I2C_GetChannelInfo(0, deviceNode);
if (status != FTDI.FT_STATUS.FT_OK)
{
throw new CommunicationException("Unable to get information about channel " + channelIndex + ". (Status: " + status + ")");
}
if (deviceNode.SerialNumber == serialNumber)
{
if (tmpChannelIndex > 0)
{
tmpChannelIndex--;
}
else
{
break;
}
}
}
if (channelIndex >= channelCount)
{
throw new CommunicationException("Unable to find channel " + deviceChannelIndex + " on device with serial number '" + serialNumber + "'.");
}
this.DeviceNode = deviceNode;
// Open channel
IntPtr handle;
status = NativeMethods_I2C.I2C_OpenChannel(channelIndex, out handle);
if (status != FTDI.FT_STATUS.FT_OK)
{
throw new CommunicationException("Unable to open I2C channel. (Status: " + status + ")");
}
this.ChannelHandle = handle;
// Configure channel
// NativeMethods.ClockRate.Standard
var config = new NativeMethods_I2C.ChannelConfig((NativeMethods_I2C.ClockRate) 10000, 1, NativeMethods_I2C.ConfigOptions.I2C_ENABLE_DRIVE_ONLY_ZERO);
status = NativeMethods_I2C.I2C_InitChannel(this.ChannelHandle, config);
if (status != FTDI.FT_STATUS.FT_OK)
{
throw new CommunicationException("Unable to initialize I2C channel. (Status: " + status + ")");
}
}));
}
