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/* Arduino WaveHC Library
* Copyright (C) 2009 by William Greiman
*
* This file is part of the Arduino WaveHC Library
*
* This Library is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This Library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with the Arduino WaveHC Library. If not, see
* <http://www.gnu.org/licenses/>.
*/
/**
* Macros and inline functions for MCP4921 DAC
*/
#ifndef mcpDac_h
#define mcpDac_h
#include <avr/io.h>
#include "OTPinDefs.h"
//------------------------------------------------------------------------------
#define mcpDacCsLow() MCP_DAC_CS_PORT &= ~_BV(MCP_DAC_CS_BIT)
#define mcpDacCsHigh() MCP_DAC_CS_PORT |= _BV(MCP_DAC_CS_BIT)
#define mcpDac2CsLow() MCP_DAC_CS_PORT &= ~_BV(MCP_DAC2_CS_BIT)
#define mcpDac2CsHigh() MCP_DAC_CS_PORT |= _BV(MCP_DAC2_CS_BIT)
#define mcpDacSckLow() MCP_DAC_SCK_PORT &= ~_BV(MCP_DAC_SCK_BIT)
#define mcpDacSckHigh() MCP_DAC_SCK_PORT |= _BV(MCP_DAC_SCK_BIT)
#define mcpDacSckPulse() {mcpDacSckHigh();mcpDacSckLow();}
#define mcpDacSdiLow() MCP_DAC_SDI_PORT &= ~_BV(MCP_DAC_SDI_BIT)
#define mcpDacSdiHigh() MCP_DAC_SDI_PORT |= _BV(MCP_DAC_SDI_BIT)
#define mcpDacSdiSet(v) if(v){mcpDacSdiHigh();}else{mcpDacSdiLow();}
// send bit b of d
#define mcpDacSendBit(d, b) {mcpDacSdiSet(d&_BV(b));mcpDacSckPulse();}
//------------------------------------------------------------------------------
// init dac I/O ports
inline void mcpDacInit(void) {
// set all to output mode
MCP_DAC_CS_DDR |= _BV(MCP_DAC_CS_BIT);
MCP_DAC2_CS_DDR |= _BV(MCP_DAC2_CS_BIT);
MCP_DAC_SCK_DDR |= _BV(MCP_DAC_SCK_BIT);
MCP_DAC_SDI_DDR |= _BV(MCP_DAC_SDI_BIT);
// chip select high
mcpDacCsHigh();
mcpDac2CsHigh();
#if USE_MCP_DAC_LDAC
// LDAC low always - use unbuffered mode
MCP_DAC_LDAC_DDR |= _BV(MCP_DAC_LDAC_BIT);
MCP_DAC_LDAC_PORT &= ~_BV(MCP_DAC_LDAC_BIT);
#endif // USE_MCP_DAC_LDAC
}
//------------------------------------------------------------------------------
// send 12 bits to dac
// trusted compiler to optimize and it does
// csLow to csHigh takes 8 - 9 usec on a 16 MHz Arduino
inline void mcpDacSend(uint16_t data) {
mcpDacCsLow();
// send DAC config bits
mcpDacSdiLow();
mcpDacSckPulse(); // DAC A
mcpDacSdiHigh();
mcpDacSckPulse(); // buffered REF
mcpDacSckPulse(); // 1X gain
mcpDacSckPulse(); // no SHDN
// send 12 data bits
mcpDacSendBit(data, 11);
mcpDacSendBit(data, 10);
mcpDacSendBit(data, 9);
mcpDacSendBit(data, 8);
mcpDacSendBit(data, 7);
mcpDacSendBit(data, 6);
mcpDacSendBit(data, 5);
mcpDacSendBit(data, 4);
mcpDacSendBit(data, 3);
mcpDacSendBit(data, 2);
mcpDacSendBit(data, 1);
mcpDacSendBit(data, 0);
mcpDacCsHigh();
}
inline void mcpDac2ASend(uint16_t data) {
mcpDac2CsLow();
// send DAC config bits
mcpDacSdiLow();
mcpDacSckPulse(); // DAC A
mcpDacSdiHigh();
mcpDacSckPulse(); // buffered REF
mcpDacSckPulse(); // 1X gain
mcpDacSckPulse(); // no SHDN
// send 12 data bits
mcpDacSendBit(data, 11);
mcpDacSendBit(data, 10);
mcpDacSendBit(data, 9);
mcpDacSendBit(data, 8);
mcpDacSendBit(data, 7);
mcpDacSendBit(data, 6);
mcpDacSendBit(data, 5);
mcpDacSendBit(data, 4);
mcpDacSendBit(data, 3);
mcpDacSendBit(data, 2);
mcpDacSendBit(data, 1);
mcpDacSendBit(data, 0);
mcpDac2CsHigh();
}
inline void mcpDac2BSend(uint16_t data) {
mcpDac2CsLow();
// send DAC config bits
mcpDacSdiHigh();
mcpDacSckPulse(); // DAC A
mcpDacSdiHigh();
mcpDacSckPulse(); // buffered REF
mcpDacSckPulse(); // 1X gain
mcpDacSckPulse(); // no SHDN
// send 12 data bits
mcpDacSendBit(data, 11);
mcpDacSendBit(data, 10);
mcpDacSendBit(data, 9);
mcpDacSendBit(data, 8);
mcpDacSendBit(data, 7);
mcpDacSendBit(data, 6);
mcpDacSendBit(data, 5);
mcpDacSendBit(data, 4);
mcpDacSendBit(data, 3);
mcpDacSendBit(data, 2);
mcpDacSendBit(data, 1);
mcpDacSendBit(data, 0);
mcpDac2CsHigh();
}
#endif //mcpDac_h