WebSVN - Projects - Blame - Rev 184 - /MoteCtrl/Sources/pc_serial

Rev	Author	Line No.	Line
178	Alpin	1	/* This file is part of MoteCtrl
		2	http://www.mikrokopter.de/ucwiki/en/MoteCtrl
		3	*/
		4
		5	//Include header files, which provide resources, pc_serial_port.c needs:
		6	#include <windows.h> //Windows API, to interface with the serial port
		7	#include <stdio.h> //Standard I/O (printf for instance)
		8
		9	#include "pc_serial_port.h"
		10
		11
		12	/*
		13	Compiler & Linker Porperties:
		14	Set "Character Set"-CompilerFlag to "Not Set" or "Multi Byte Character Set" to
		15	avoid Errors about Windows API functions that can handle Unicode paramters.
		16	In Visual Studio: Properties of Project -> Configuration Properties -> General
		17	*/
		18
		19
		20	HANDLE hCom; //Handle, which contains inf about the opened Device File
		21	//(the opened COM-Port, returned by CreateFile function)
		22
		23	//Initialize & Configure COMx-Port
		24	//return value: EXIT_FAILURE=1, EXIT_SUCCESS=0 (stdlib macros)
		25	int init_com_port(int comNumber) {
		26
		27	DCB dcb; //Device Control Block, contains Configuration for COM-Port
184	Alpin	28	char comPort[6] = {'C','O','M'}; //Number and String Terminator to be added
178	Alpin	29	int fSuccess; //Stores inf about file-actions (action succeeded or failed)
		30	COMMTIMEOUTS timeouts; //Struct, which stores inf about the timeout
		31	//behaviour of the COM-Port
		32
		33	//Get the Com-Port Number:
184	Alpin	34	if( (comNumber>0) && (comNumber<10) ) {
178	Alpin	35
184	Alpin	36	comPort[3] = 48 + comNumber; //COMx (x is ASCII coded)
		37	comPort[4] = 0; //add string Terminator 'NUL'
		38	comPort[5] = 0;
		39	printf("-->using %s\n", comPort);
		40	}
		41
		42	else {
		43	if(comNumber>=10 && comNumber<=99) {
		44
		45	comPort[3] = 48 + (comNumber/10);
		46	comPort[4] = 48 + (comNumber%10);
		47	comPort[5] = 0;
		48	printf("-->using %s\n", comPort);
		49	}
		50
		51	else {
		52	printf("COM Port must be between 1 and 99\n");
		53	return EXIT_FAILURE;
		54	}
		55	}
		56
178	Alpin	57	//Create Device File, initialize serial Port:
		58	hCom = CreateFile( comPort, //open COMx Device (pointer to comPort-String)
		59	GENERIC_READ \| GENERIC_WRITE, //write/read permisions
		60	0, // must be opened with exclusive-access
		61	NULL, // default security
		62	OPEN_EXISTING, // must use OPEN_EXISTING
		63	0, // no overlapping
		64	NULL // hTemplate must be NULL for comm devices
		65	);
		66
		67	//Check, if CreateFile succeeded:
		68	if (hCom == INVALID_HANDLE_VALUE) {
		69	printf ("***ERR: CreateFile failed with error %d.\n", GetLastError());
		70	return EXIT_FAILURE;
		71	}
		72
		73	//Get the currently active Device Control Block (DCB) for the COMx:
		74	SecureZeroMemory(&dcb, sizeof(DCB)); //initialize entire dcb-struct with zeros
		75	dcb.DCBlength = sizeof(DCB);
		76	fSuccess = GetCommState(hCom, &dcb); //write the current configuration to
		77	//our dcb-struct
		78
		79	//GetCommState returns 0, if error occured while getting the DCB
		80	if (!fSuccess) {
		81	printf ("***ERR: GetCommState failed with error %d.\n", GetLastError());
		82	return EXIT_FAILURE;
		83	}
		84
		85	/*Change the values of the obtained dcb-struct to match the config of the
		86	*Mikrokopter. Currently the FlightControl communicates at:
		87	57600 Baud (bps), 8 Data bits, no parity bit, 1 stop bit /
		88
		89	dcb.BaudRate = CBR_57600; // Set Baudrate
		90	dcb.ByteSize = 8; // data size, transmit and receive
		91	dcb.Parity = NOPARITY; // no parity bit
		92	dcb.StopBits = ONESTOPBIT; // one stop bit
		93
		94	//Send reconfigured dcb back to COMx Device-File:
		95	fSuccess = SetCommState(hCom, &dcb);
		96
		97	//SetCommState returns a 0, if error occured while setting the DCB for COMx
		98	if (!fSuccess) {
		99	printf ("***ERR: SetCommState failed with error %d.\n", GetLastError());
		100	return EXIT_FAILURE;
		101	}
		102
		103	//Configure the Read-Timeout behaviour of the initialized COMx-Port:
		104
		105	/* The following Read-Timeout config determines the behaviour of the
		106	ReadFile cmd (applied to the initialized COMx-Port):
		107	If a Byte is in the Hardware UART-Buffer of the initialized COM-Port and
		108	the ReadFile function is called, this byte is read. If theres no byte in
		109	the UART-InputBuffer and the ReadFile function is called, the ReadFile
		110	function will return immediatly (BytesRead parameter is zero then).
		111	*/
		112	timeouts.ReadIntervalTimeout = MAXDWORD;
		113	timeouts.ReadTotalTimeoutMultiplier = 0;
		114	timeouts.ReadTotalTimeoutConstant = 0;
		115
		116	//Send the Timeout-Config to the COM-Port:
		117	fSuccess = SetCommTimeouts (hCom, &timeouts);
		118
		119	//Check, if setting the timeout-settings was successfull:
		120	if(!fSuccess) {
		121	printf("***ERR: SetCommTimeouts failed with error %d.\n", GetLastError());
		122	return EXIT_FAILURE;
		123	}
		124
		125
		126	//Initialization & Configuration of COMx done!
		127	return EXIT_SUCCESS;
		128	}
		129
		130
		131	//Function which reads 1 Byte of the Rx-Buffer of the initialized COM-Port:
		132	//Return value: Number of the bytes read (should be 0 or 1)
		133	int getCharFromCom (char* inputBuffer) {
		134
		135	int numOfBytesRead;
		136	ReadFile (hCom, inputBuffer, 1, &numOfBytesRead, NULL);
		137	//read char is stored in the passed char-buffer
		138
		139	return numOfBytesRead;
		140
		141	}
		142
		143
		144	//Function which writes [length] Byte to the Tx-Buffer of the initialized COM-Port:
		145	//Returns something>0 if write failed, 0 if successfull
		146	int sendStringToCom (char* toSend, int length) {
		147
		148	int numOfBytesWritten;
		149
		150	//write char to which the passed char-pointer points to
		151	return WriteFile (hCom, toSend, length, &numOfBytesWritten, NULL);
		152	}

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(root)/MoteCtrl/Sources/pc_serial_port.c @ 1563 - Rev 184