Code:
#include <windows.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "cf_packet.h"
HANDLE hPort;
HANDLE handle;
COMMAND_PACKET
outgoing_response;
BOOL WriteByte(BYTE bybyte)
{
DWORD iBytesWritten=0;
DWORD iBytesToRead = 1;
if(WriteFile(hPort,(LPCVOID)
&bybyte,iBytesToRead,&iBytesWritten,NULL)==0)
return FALSE;
else return TRUE;
}
BOOL WriteString(const void *instring, int length)
{
int index;
BYTE *inbyte = (BYTE *) instring;
for(index = 0; index< length; ++index)
{
if (WriteByte(inbyte[index]) == FALSE)
return FALSE;
}
return TRUE;
}
BOOL ReadByte(BYTE resp)
{
BOOL bReturn = TRUE;
BYTE rx;
DWORD dwBytesTransferred=0;
if (ReadFile (hPort, &rx, 1, &dwBytesTransferred, 0)> 0)
{
if (dwBytesTransferred == 1)
{
resp=rx;
bReturn = TRUE;
}
else bReturn = FALSE;
}
else bReturn = FALSE;
return bReturn;
}
BOOL ReadString(void *outstring, int *length)
{
BYTE data;
BYTE dataout[4096]={0};
int index = 0;
while(ReadByte(data)== TRUE)
{
dataout[index++] = data;
}
memcpy(outstring, dataout, index);
*length = index;
return TRUE;
}
void ClosePort()
{
CloseHandle(hPort);
return;
}
HANDLE ConfigureSerialPort(LPCSTR lpszPortName)
{
HANDLE handle = NULL;
DWORD dwError;
DCB PortDCB;
COMMTIMEOUTS CommTimeouts;
// Open the serial port.
handle = CreateFile (lpszPortName, // Pointer to the name of the port
GENERIC_READ | GENERIC_WRITE,
// Access (read-write) mode
0, // Share mode
NULL, // Pointer to the security attribute
OPEN_EXISTING, // How to open the serial port
0, // Port attributes
NULL); // Handle to port with attribute to copy
// Initialize the DCBlength member.
PortDCB.DCBlength = sizeof (DCB);
// Get the default port setting information.
GetCommState (handle, &PortDCB);
// Change the DCB structure settings.
PortDCB.BaudRate = 115200; // Current baud
PortDCB.fBinary = TRUE; // Binary mode; no EOF check
PortDCB.fParity = TRUE; // Enable parity checking
PortDCB.fOutxCtsFlow = FALSE; // No CTS output flow control
PortDCB.fOutxDsrFlow = FALSE; // No DSR output flow control
PortDCB.fDtrControl = DTR_CONTROL_ENABLE; // DTR flow control type
PortDCB.fDsrSensitivity = FALSE; // DSR sensitivity
PortDCB.fTXContinueOnXoff = TRUE; // XOFF continues Tx
PortDCB.fOutX = FALSE; // No XON/XOFF out flow control
PortDCB.fInX = FALSE; // No XON/XOFF in flow control
PortDCB.fErrorChar = FALSE; // Disable error replacement
PortDCB.fNull = FALSE; // Disable null stripping
PortDCB.fRtsControl = RTS_CONTROL_ENABLE; // RTS flow control
PortDCB.fAbortOnError = FALSE; // Do not abort reads/writes on error
PortDCB.ByteSize = 8; // Number of bits/byte, 4-8
PortDCB.Parity = NOPARITY; // 0-4=no,odd,even,mark,space
PortDCB.StopBits = ONESTOPBIT; // 0,1,2 = 1, 1.5, 2
// Configure the port according to the specifications of the DCB structure.
if (!SetCommState (handle, &PortDCB))
{
printf("Could not configure serial port\n");
return NULL;
}
// Retrieve the time-out parameters for all read and write operations
// on the port.
GetCommTimeouts (handle, &CommTimeouts);
// Change the COMMTIMEOUTS structure settings.
CommTimeouts.ReadIntervalTimeout = MAXDWORD;
CommTimeouts.ReadTotalTimeoutMultiplier = 0;
CommTimeouts.ReadTotalTimeoutConstant = 0;
CommTimeouts.WriteTotalTimeoutMultiplier = 0;
CommTimeouts.WriteTotalTimeoutConstant = 0;
if (!SetCommTimeouts (handle, &CommTimeouts))
{
printf("Could not set timeouts\n");
return NULL;
}
printf("%s", lpszPortName);
return handle;
}
void send_packet(void)
{
//In order to send the entire packet in one call to "write()", we
//need to place the CRC packed against the data. If data_length
//happens to be MAX_DATA_LENGTH, then the position of the CRC is
//outgoing_response.CRC (like you would expect), but if data_length
//is less, the CRC moves into the data area, packed into the first
//unused data position.
//
//Create a pointer to the first unused data positions.
word
*packed_CRC_position;
packed_CRC_position=
(word *)&outgoing_response.data[outgoing_response.data_length];
*packed_CRC_position=
get_crc((ubyte *)&outgoing_response,outgoing_response.data_length+2,0xFFFF);
//command, length, data[data_length], crc, crc
//SendData((ubyte *)&outgoing_response,outgoing_response.data_length+4);
}
word get_crc(ubyte *bufptr,word len,word seed)
{
//CRC lookup table to avoid bit-shifting loops.
static const word crcLookupTable[256] =
{0x00000,0x01189,0x02312,0x0329B,0x04624,0x057AD,0x06536,0x074BF,
0x08C48,0x09DC1,0x0AF5A,0x0BED3,0x0CA6C,0x0DBE5,0x0E97E,0x0F8F7,
0x01081,0x00108,0x03393,0x0221A,0x056A5,0x0472C,0x075B7,0x0643E,
0x09CC9,0x08D40,0x0BFDB,0x0AE52,0x0DAED,0x0CB64,0x0F9FF,0x0E876,
0x02102,0x0308B,0x00210,0x01399,0x06726,0x076AF,0x04434,0x055BD,
0x0AD4A,0x0BCC3,0x08E58,0x09FD1,0x0EB6E,0x0FAE7,0x0C87C,0x0D9F5,
0x03183,0x0200A,0x01291,0x00318,0x077A7,0x0662E,0x054B5,0x0453C,
0x0BDCB,0x0AC42,0x09ED9,0x08F50,0x0FBEF,0x0EA66,0x0D8FD,0x0C974,
0x04204,0x0538D,0x06116,0x0709F,0x00420,0x015A9,0x02732,0x036BB,
0x0CE4C,0x0DFC5,0x0ED5E,0x0FCD7,0x08868,0x099E1,0x0AB7A,0x0BAF3,
0x05285,0x0430C,0x07197,0x0601E,0x014A1,0x00528,0x037B3,0x0263A,
0x0DECD,0x0CF44,0x0FDDF,0x0EC56,0x098E9,0x08960,0x0BBFB,0x0AA72,
0x06306,0x0728F,0x04014,0x0519D,0x02522,0x034AB,0x00630,0x017B9,
0x0EF4E,0x0FEC7,0x0CC5C,0x0DDD5,0x0A96A,0x0B8E3,0x08A78,0x09BF1,
0x07387,0x0620E,0x05095,0x0411C,0x035A3,0x0242A,0x016B1,0x00738,
0x0FFCF,0x0EE46,0x0DCDD,0x0CD54,0x0B9EB,0x0A862,0x09AF9,0x08B70,
0x08408,0x09581,0x0A71A,0x0B693,0x0C22C,0x0D3A5,0x0E13E,0x0F0B7,
0x00840,0x019C9,0x02B52,0x03ADB,0x04E64,0x05FED,0x06D76,0x07CFF,
0x09489,0x08500,0x0B79B,0x0A612,0x0D2AD,0x0C324,0x0F1BF,0x0E036,
0x018C1,0x00948,0x03BD3,0x02A5A,0x05EE5,0x04F6C,0x07DF7,0x06C7E,
0x0A50A,0x0B483,0x08618,0x09791,0x0E32E,0x0F2A7,0x0C03C,0x0D1B5,
0x02942,0x038CB,0x00A50,0x01BD9,0x06F66,0x07EEF,0x04C74,0x05DFD,
0x0B58B,0x0A402,0x09699,0x08710,0x0F3AF,0x0E226,0x0D0BD,0x0C134,
0x039C3,0x0284A,0x01AD1,0x00B58,0x07FE7,0x06E6E,0x05CF5,0x04D7C,
0x0C60C,0x0D785,0x0E51E,0x0F497,0x08028,0x091A1,0x0A33A,0x0B2B3,
0x04A44,0x05BCD,0x06956,0x078DF,0x00C60,0x01DE9,0x02F72,0x03EFB,
0x0D68D,0x0C704,0x0F59F,0x0E416,0x090A9,0x08120,0x0B3BB,0x0A232,
0x05AC5,0x04B4C,0x079D7,0x0685E,0x01CE1,0x00D68,0x03FF3,0x02E7A,
0x0E70E,0x0F687,0x0C41C,0x0D595,0x0A12A,0x0B0A3,0x08238,0x093B1,
0x06B46,0x07ACF,0x04854,0x059DD,0x02D62,0x03CEB,0x00E70,0x01FF9,
0x0F78F,0x0E606,0x0D49D,0x0C514,0x0B1AB,0x0A022,0x092B9,0x08330,
0x07BC7,0x06A4E,0x058D5,0x0495C,0x03DE3,0x02C6A,0x01EF1,0x00F78};
//Initial CRC value is 0x0FFFF.
register word
newCrc;
newCrc=seed;
//This algorithim is based on the IrDA LAP example.
while(len--)
newCrc = (newCrc >> 8) ^ crcLookupTable[(newCrc ^ *bufptr++) & 0xff];
//Make this crc match the one's complement that is sent in the packet.
return(~newCrc);
}
void SendData(unsigned char *data,int length)
{
dword
bytes_written;
bytes_written=0;
if(handle)
{
if((bytes_written=write(handle, data, length)) != length)
printf("SendData(): system call \"write()\" return error.\n Asked for %d bytes to be written, but %d bytes reported as written.\n",
length,(int)bytes_written);
}
else
printf("SendData(): \"handle\" is null\n");
}
int main(void)
{
// Can also use COM2, COM3 or COM4 here
hPort = ConfigureSerialPort("COM1");
if(hPort == NULL)
{
printf("Com port configuration failed\n");
return -1;
}
// Call your ReadString and WriteString functions here
outgoing_response.command = 31;
outgoing_response.data[0]=0; //col
outgoing_response.data[1]=0; //row
memcpy(&outgoing_response.data[2],">>>This is line 1<<<",20);
outgoing_response.data_length = 22; //the col & row position + the 20 char data length
send_packet();
getchar();
getchar();
ClosePort();
return 0;
}
Any input would be greatly appreciated