a83d64ea6c
This is a general tidyup to detach this fork better from Gordon, who was (and perhaps still is) completely inundated with WiringPi-related support questions. This changeset includes a number of tweaks which should reduce support burden on Gordon. I believe they are essential if we plan to release a new debian package. They should - hopefully - not reduce or make ambiguous the origins of this code while achieving the above. * Remove Gordon's email address from all source files to avoid support queries finding their way to him * Update wiringPi URLs to the GitHub repository to try and keep bugs/issues within the fork * Bump version to 2.70 ready for a debian package release * Update debian package maintainer info, add bugs & homepage URLs to this repository
77 lines
2.1 KiB
C
77 lines
2.1 KiB
C
/*
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* mcp4802.c:
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* Extend wiringPi with the MCP4802 SPI Digital to Analog convertor
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* Copyright (c) 2012-2013 Gordon Henderson
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***********************************************************************
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* This file is part of wiringPi:
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* https://github.com/WiringPi/WiringPi/
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*
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* wiringPi is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as
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* published by the Free Software Foundation, either version 3 of the
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* License, or (at your option) any later version.
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*
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* wiringPi is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with wiringPi.
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* If not, see <http://www.gnu.org/licenses/>.
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***********************************************************************
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*/
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#include <wiringPi.h>
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#include <wiringPiSPI.h>
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#include "mcp4802.h"
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/*
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* myAnalogWrite:
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* Write analog value on the given pin
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*********************************************************************************
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*/
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static void myAnalogWrite (struct wiringPiNodeStruct *node, int pin, int value)
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{
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unsigned char spiData [2] ;
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unsigned char chanBits, dataBits ;
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int chan = pin - node->pinBase ;
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if (chan == 0)
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chanBits = 0x30 ;
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else
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chanBits = 0xB0 ;
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chanBits |= ((value >> 4) & 0x0F) ;
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dataBits = ((value << 4) & 0xF0) ;
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spiData [0] = chanBits ;
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spiData [1] = dataBits ;
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wiringPiSPIDataRW (node->fd, spiData, 2) ;
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}
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/*
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* mcp4802Setup:
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* Create a new wiringPi device node for an mcp4802 on the Pi's
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* SPI interface.
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*********************************************************************************
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*/
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int mcp4802Setup (const int pinBase, int spiChannel)
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{
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struct wiringPiNodeStruct *node ;
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if (wiringPiSPISetup (spiChannel, 1000000) < 0)
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return FALSE ;
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node = wiringPiNewNode (pinBase, 2) ;
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node->fd = spiChannel ;
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node->analogWrite = myAnalogWrite ;
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return TRUE ;
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}
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