我通过机械 VB 到 C# 的翻译器运行 Hippy 的 VB 版本,发现了一个关键区别。FT_WRITE 使用字符串将数据传递给非托管代码。C# 类使用指向字节数组的 IPtr。
这个版本适用于我:
using System;
using System.Runtime.InteropServices;
using System.Threading;
// based on Hippy's VB Example
// http://members.westnet.com.au/rowanmac/opendmx.html#tx
// Working link: https://web.archive.org/web/20150217155014/http://members.westnet.com.au:80/rowanmac/opendmx.html
namespace Test
{
class Program
{
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_Open(short intDeviceNumber, ref int lngHandle);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_Close(int lngHandle);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetDivisor(int lngHandle, int div);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_Read(int lngHandle, string lpszBuffer, int lngBufferSize, ref int lngBytesReturned);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_Write(int lngHandle, string lpszBuffer, int lngBufferSize, ref int lngBytesWritten);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_Write(int lngHandle, IntPtr lpBuffer, int lngBufferSize, ref int lngBytesWritten);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetBaudRate(int lngHandle, int lngBaudRate);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetDataCharacteristics(int lngHandle, byte byWordLength, byte byStopBits, byte byParity);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetFlowControl(int lngHandle, short intFlowControl, byte byXonChar, byte byXoffChar);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_ResetDevice(int lngHandle);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetDtr(int lngHandle);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_ClrDtr(int lngHandle);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetRts(int lngHandle);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_ClrRts(int lngHandle);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_GetModemStatus(int lngHandle, ref int lngModemStatus);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_Purge(int lngHandle, int lngMask);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_GetStatus(int lngHandle, ref int lngRxBytes, ref int lngTxBytes, ref int lngEventsDWord);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_GetQueueStatus(int lngHandle, ref int lngRxBytes);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_GetEventStatus(int lngHandle, ref int lngEventsDWord);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetChars(int lngHandle, byte byEventChar, byte byEventCharEnabled, byte byErrorChar, byte byErrorCharEnabled);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetTimeouts(int lngHandle, int lngReadTimeout, int lngWriteTimeout);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetBreakOn(int lngHandle);
[DllImport("FTD2XX.DLL", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int FT_SetBreakOff(int lngHandle);
// FTDI Constants
const short FT_OK = 0;
const short FT_INVALID_HANDLE = 1;
const short FT_DEVICE_NOT_FOUND = 2;
const short FT_DEVICE_NOT_OPENED = 3;
const short FT_IO_ERROR = 4;
const short FT_INSUFFICIENT_RESOURCES = 5;
// Word Lengths
const byte FT_BITS_8 = 8;
// Stop Bits
const byte FT_STOP_BITS_2 = 2;
// Parity
const byte FT_PARITY_NONE = 0;
// Flow Control
const byte FT_FLOW_NONE = 0x0;
// Purge rx and tx buffers
const byte FT_PURGE_RX = 1;
const byte FT_PURGE_TX = 2;
public static int handle=0;
public static byte[] buffer = new byte[4]; // can be up to 512, shorter is faster
private static string lpszBuffer=""+ (char) 0 + (char) 64 + (char) 64+ (char) 0;
static void Main(string[] args)
{
init();
}
public static string init()
{
short n = 0;
// ==== ATTEMPT TO OPEN DEVICE ====
if (FT_Open(n, ref handle) != FT_OK)
{
return "FTTD Not Found";
}
// ==== PREPARE DEVICE FOR DMX TRANSMISSION ====
// reset the device
if (FT_ResetDevice(handle) != FT_OK)
{
return "Failed To Reset Device!";
}
// get an ID from the widget from jumpers
// GetID(ref n);
// set the baud rate
if (FT_SetDivisor(handle, 12) != FT_OK)
{
return "Failed To Set Baud Rate!";
}
// shape the line
if (FT_SetDataCharacteristics(handle, FT_BITS_8, FT_STOP_BITS_2, FT_PARITY_NONE) != FT_OK)
{
return "Failed To Set Data Characteristics!";
}
// no flow control
if (FT_SetFlowControl(handle, FT_FLOW_NONE, 0, 0) != FT_OK)
{
return "Failed to set flow control!";
}
// set bus transiever to transmit enable
if (FT_ClrRts(handle) != FT_OK)
{
return "Failed to set RS485 to send!";
}
// Clear TX & RX buffers
if (FT_Purge(handle, FT_PURGE_TX) != FT_OK)
{
return "Failed to purge TX buffer!";
}
// empty buffers
if (FT_Purge(handle, FT_PURGE_RX) != FT_OK)
{
return "Failed to purge RX buffer!";
}
setDmxValue(0, 0); // should always be zero
setDmxValue(1, 64);
setDmxValue(2, 64);
setDmxValue(3, 0);
Thread thread = new Thread(new ThreadStart(writeDataThread));
thread.Start();
return "Ok";
}
// init
public static void setDmxValue(int channel, byte value)
{
buffer[channel] = value;
lpszBuffer="";
for (int i = 0; i < buffer.Length; ++i)
{
lpszBuffer += (char)buffer[i];
}
}
public static void writeDataThread()
{
bool done = false;
int lngBytesWritten=0;
while (!done)
{
FT_SetBreakOn(handle);
FT_SetBreakOff(handle);
FT_Write(handle, lpszBuffer, buffer.Length, ref lngBytesWritten);
System.Threading.Thread.Sleep(50);
}
}
}
}