Equivalent of C unsigned char array in c# using PInvoke

I posted yesterday about how I am converting a C program to C# as my first C# project here: Convert from C to C#, or make DLL?. I have made a lot of progress, but I am stuck on a section. I am not sure how I should go about recreating this unsigned char array C Code: ``` unsigned char state_buf[5125]; //-------------------------------------------------------------------------- // Main of iSerial64 // void main(int argc, char **argv) { char refresh,buf[200]; short flag,i,didsetup=0; short ROM[9]; short PortNum,PortType; long SHandle; char serialtmp[2], serial[10][17]; int j = -1; ``` .... This is the function in C# that takes state_buf using PInvoke http://files.maximintegrated.com/sia_bu/licensed/docs/1-wire_sdk_win/TMEX/romm1rxq.html C# Code that I am using to import the function from the api: ``` [DllImport("IBFS64.dll")] public static extern short TMRom( int session_handle, byte state_buf, [MarshalAs(UnmanagedType.LPStr)]StringBuilder ROM ); ``` I saw that byte was the C# equivalent, but I am not fully sure how to use it. You guys have been so helpful thus far, and I am really pleased with the progress I am making on this. This is what I have gotten done in C# since yesterday: ``` using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Runtime.InteropServices; namespace PInvokeTest { class Program { static void Main(string[] args) { int session_handle = 0; int result = 0; int flag = 0; int didsetup = 0; int defPort = 0; int i = 0, j = -1; short type_test = 0; byte state_buf = 0; short port_num = 0, port_type = 1; StringBuilder ID_buf = new StringBuilder(); StringBuilder serial = new StringBuilder(); StringBuilder serialtmp = new StringBuilder(); StringBuilder ROM = new StringBuilder(); //result = TMSearch(session_handle, state_buffer, 1, 1, 0xEC); defPort = TMReadDefaultPort(out port_num,out port_type); if (defPort == 1) { Console.Write("Default Device: "); switch (port_type) { case 1: Console.Write("DS9097E serial adapter "); break; case 2: Console.Write("Parallel adapter "); break; case 5: Console.Write("DS90907U serial adapter "); break; case 6: Console.Write("DS9490 USB adapter "); break; } Console.Write("on port # {0}", port_num); } else Console.Write("No Device found"); // get the TMEX driver version Get_Version(ID_buf); Console.WriteLine("\nDriver: {0}", ID_buf); type_test = TMGetTypeVersion(port_type, ID_buf); if (type_test < 0) { Console.WriteLine("\nNo Hardware Driver for this type found!\n"); Console.Write("Press any key to exit"); Console.ReadKey(); Environment.Exit(0); } else Console.WriteLine("Driver Found"); // check for valid range of PortNum if ((port_num < 1) || (port_num > 15)) { Console.WriteLine("ERROR, invalid port requested: {0}\n", port_num); Console.Write("Press any key to exit"); Console.ReadKey(); Environment.Exit(0); } do { // get a session handle to the requested port session_handle = TMExtendedStartSession(port_num, port_type, IntPtr.Zero); if (session_handle > 0) { // check to see if TMSetup has been done once if (didsetup == 0) { flag = TMSetup(session_handle); if (flag == 1 || flag == 2) { Console.Write("TMSetup complete {0}", flag); didsetup = 1; } else { Console.Write("ERROR doing setup {0}", flag); break; } } else { //j was added to keep track of the serial number strings j++; //memset(serial[j], 0, strlen(serial[j])); flag = TMNext(session_handle, state_buf); if (flag > 0) { //ROM[0] = 0; flag = TMRom(session_handle, state_buf, ROM); for (i = 7; i >= 0; i--) { //This section was changed from the original //copies raw number into string //sprintf(serialtmp, "%02X", ROM[i]); //strcat(serial[j], serialtmp); } Console.WriteLine("{0} \n", serial[j]); } else Console.WriteLine("end of search\n"); } // close the opened session TMEndSession(session_handle); } } while (flag > 0); Console.ReadKey(); } [DllImport("IBFS64.dll")] public static extern int TMExtendedStartSession( short PortNum, short PortType, IntPtr EnhancedOptions ); [DllImport("IBFS64.dll")] public static extern short TMSearch( int session_handle, byte state_buffer, short p1, short p2, short p3 ); [DllImport("IBFS64.dll")] public static extern short TMReadDefaultPort( out short port_num, out short port_type ); [DllImport("IBFS64.dll")] public static extern short Get_Version( [MarshalAs(UnmanagedType.LPStr)]StringBuilder ID_buf ); [DllImport("IBFS64.dll")] public static extern short TMGetTypeVersion( short port_type, [MarshalAs(UnmanagedType.LPStr)]StringBuilder ID_buf ); [DllImport("IBFS64.dll")] public static extern short TMSetup( int session_handle ); [DllImport("IBFS64.dll")] public static extern short TMNext( int session_handle, byte state_buf ); [DllImport("IBFS64.dll")] public static extern short TMRom( int session_handle, byte state_buf, [MarshalAs(UnmanagedType.LPStr)]StringBuilder ROM ); [DllImport("IBFS64.dll")] public static extern short TMEndSession( int session_handle ); } } ``` Let me know if there is anything I should change. I appreciate the help!