gitified_old_clb_svn/sw/embedded/WRPC/sockitowm/owtran.c

//---------------------------------------------------------------------------
// Copyright (C) 1999 Dallas Semiconductor Corporation, All Rights Reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
// IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES
// OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
// OTHER DEALINGS IN THE SOFTWARE.
//
// Except as contained in this notice, the name of Dallas Semiconductor
// shall not be used except as stated in the Dallas Semiconductor
// Branding Policy.
//---------------------------------------------------------------------------
//
// owTran.C - Transport functions for 1-Wire devices.
//
// Version: 2.01
//
// History: 1.03 -> 2.00 Changed 'MLan' to 'ow'. Added support for
// multiple ports.
// 2.00 -> 2.01 Added support for owError library
//

#include "ownet.h"

//--------------------------------------------------------------------------
// The 'owBlock' transfers a block of data to and from the
// 1-Wire Net with an optional reset at the begining of communication.
// The result is returned in the same buffer.
//
// 'do_reset' - cause a owTouchReset to occure at the begining of
// communication TRUE(1) or not FALSE(0)
// 'tran_buf' - pointer to a block of unsigned
// chars of length 'TranferLength' that will be sent
// to the 1-Wire Net
// 'tran_len' - length in bytes to transfer
// Supported devices: all
//
// Returns: TRUE (1) : The optional reset returned a valid
// presence (do_reset == TRUE) or there
// was no reset required.
// FALSE (0): The reset did not return a valid prsence
// (do_reset == TRUE).
//
// The maximum tran_len is 160
//
SMALLINT owBlock(int portnum, SMALLINT do_reset, uchar * tran_buf,
		 SMALLINT tran_len)
{
	uchar i;

	// check for a block too big
	if (tran_len > 160) {
		OWERROR(OWERROR_BLOCK_TOO_BIG);
		return FALSE;
	}
	// check if need to do a owTouchReset first
	if (do_reset) {
		if (!owTouchReset(portnum)) {
			OWERROR(OWERROR_NO_DEVICES_ON_NET);
			return FALSE;
		}
	}
	// send and receive the buffer
	for (i = 0; i < tran_len; i++)
		tran_buf[i] = (uchar) owTouchByte(portnum, tran_buf[i]);

	return TRUE;
}

//--------------------------------------------------------------------------
// Write a byte to an EPROM 1-Wire device.
//
// Supported devices: crc_type=0(CRC8)
// DS1982
// crc_type=1(CRC16)
// DS1985, DS1986, DS2407
//
// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
// indicate the symbolic port number.
// 'write_byte' - byte to program
// 'addr' - address of byte to program
// 'write_cmd' - command used to write (0x0F reg mem, 0x55 status)
// 'crc_type' - CRC used (0 CRC8, 1 CRC16)
// 'do_access' - Flag to access device for each byte
// (0 skip access, 1 do the access)
// WARNING, only use do_access=0 if programing the NEXT
// byte immediatly after the previous byte.
//
// Returns: >=0 success, this is the resulting byte from the program
// effort
// -1 error, device not connected or program pulse voltage
// not available
//
SMALLINT owProgramByte(int portnum, SMALLINT write_byte, int addr,
		       SMALLINT write_cmd, SMALLINT crc_type,
		       SMALLINT do_access)
{
	ushort lastcrc16;
	uchar lastcrc8;

	// optionally access the device
	if (do_access) {
		if (!owAccess(portnum)) {
			OWERROR(OWERROR_ACCESS_FAILED);
			return -1;
		}
		// send the write command
		if (!owWriteByte(portnum, write_cmd)) {
			OWERROR(OWERROR_WRITE_BYTE_FAILED);
			return -1;
		}
		// send the address
		if (!owWriteByte(portnum, addr & 0xFF)
		    || !owWriteByte(portnum, addr >> 8)) {
			OWERROR(OWERROR_WRITE_BYTE_FAILED);
			return -1;
		}
	}
	// send the data to write
	if (!owWriteByte(portnum, write_byte)) {
		OWERROR(OWERROR_WRITE_BYTE_FAILED);
		return -1;
	}
	// read the CRC
	if (crc_type == 0) {
		// calculate CRC8
		if (do_access) {
			setcrc8(portnum, 0);
			docrc8(portnum, (uchar) write_cmd);
			docrc8(portnum, (uchar) (addr & 0xFF));
			docrc8(portnum, (uchar) (addr >> 8));
		} else
			setcrc8(portnum, (uchar) (addr & 0xFF));

		docrc8(portnum, (uchar) write_byte);
		// read and calculate the read crc
		lastcrc8 = docrc8(portnum, (uchar) owReadByte(portnum));
		// crc should now be 0x00
		if (lastcrc8 != 0) {
			OWERROR(OWERROR_CRC_FAILED);
			return -1;
		}
	} else {
		// CRC16
		if (do_access) {
			setcrc16(portnum, 0);
			docrc16(portnum, (ushort) write_cmd);
			docrc16(portnum, (ushort) (addr & 0xFF));
			docrc16(portnum, (ushort) (addr >> 8));
		} else
			setcrc16(portnum, (ushort) addr);
		docrc16(portnum, (ushort) write_byte);
		// read and calculate the read crc
		docrc16(portnum, (ushort) owReadByte(portnum));
		lastcrc16 = docrc16(portnum, (ushort) owReadByte(portnum));
		// crc should now be 0xB001
		if (lastcrc16 != 0xB001)
			return -1;
	}

	// send the program pulse
	if (!owProgramPulse(portnum)) {
		OWERROR(OWERROR_PROGRAM_PULSE_FAILED);
		return -1;
	}
	// read back and return the resulting byte
	return owReadByte(portnum);
}