Marlin_Firmware/Marlin/dac_mcp4728.cpp
2016-10-07 15:57:24 -05:00

145 lines
4.4 KiB
C++

/**
* Marlin 3D Printer Firmware
* Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
*
* Based on Sprinter and grbl.
* Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
*
* This program 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 program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
/**
* mcp4728.cpp - Arduino library for MicroChip MCP4728 I2C D/A converter
*
* For implementation details, please take a look at the datasheet:
* http://ww1.microchip.com/downloads/en/DeviceDoc/22187a.pdf
*
* For discussion and feedback, please go to:
* http://arduino.cc/forum/index.php/topic,51842.0.html
*/
#include "dac_mcp4728.h"
#if ENABLED(DAC_STEPPER_CURRENT)
uint16_t mcp4728_values[XYZE];
/**
* Begin I2C, get current values (input register and eeprom) of mcp4728
*/
void mcp4728_init() {
Wire.begin();
Wire.requestFrom(int(DAC_DEV_ADDRESS), 24);
while (Wire.available()) {
char deviceID = Wire.read(),
hiByte = Wire.read(),
loByte = Wire.read();
if (!(deviceID & 0x08))
mcp4728_values[(deviceID & 0x30) >> 4] = word((hiByte & 0x0F), loByte);
}
}
/**
* Write input resister value to specified channel using fastwrite method.
* Channel : 0-3, Values : 0-4095
*/
uint8_t mcp4728_analogWrite(uint8_t channel, uint16_t value) {
mcp4728_values[channel] = value;
return mcp4728_fastWrite();
}
/**
* Write all input resistor values to EEPROM using SequencialWrite method.
* This will update both input register and EEPROM value
* This will also write current Vref, PowerDown, Gain settings to EEPROM
*/
uint8_t mcp4728_eepromWrite() {
Wire.beginTransmission(DAC_DEV_ADDRESS);
Wire.write(SEQWRITE);
for (uint8_t channel = 0; channel < COUNT(channel); channel++) {
Wire.write(DAC_STEPPER_VREF << 7 | DAC_STEPPER_GAIN << 4 | highByte(mcp4728_values[channel]));
Wire.write(lowByte(mcp4728_values[channel]));
}
return Wire.endTransmission();
}
/**
* Write Voltage reference setting to all input regiters
*/
uint8_t mcp4728_setVref_all(uint8_t value) {
Wire.beginTransmission(DAC_DEV_ADDRESS);
Wire.write(GAINWRITE | (value ? 0x0F : 0x00));
return Wire.endTransmission();
}
/**
* Write Gain setting to all input regiters
*/
uint8_t mcp4728_setGain_all(uint8_t value) {
Wire.beginTransmission(DAC_DEV_ADDRESS);
Wire.write(GAINWRITE | (value ? 0x0F : 0x00));
return Wire.endTransmission();
}
/**
* Return Input Regiter value
*/
uint16_t mcp4728_getValue(uint8_t channel) { return mcp4728_values[channel]; }
/**
* Steph: Might be useful in the future
* Return Vout
*
uint16_t mcp4728_getVout(uint8_t channel) {
uint32_t vref = 2048,
vOut = (vref * mcp4728_values[channel] * (_DAC_STEPPER_GAIN + 1)) / 4096;
if (vOut > defaultVDD) vOut = defaultVDD;
return vOut;
}
*/
/* Returns DAC values as a 0-100 percentage of drive strength */
uint16_t mcp4728_getDrvPct(uint8_t channel) { return uint16_t(100.0 * mcp4728_values[channel] / (DAC_STEPPER_MAX) + 0.5); }
/* Recieves all Drive strengths as 0-100 percent values, updates DAC Values array and calls fastwrite to update the DAC */
void mcp4728_setDrvPct(int16_t pct[XYZE]) {
LOOP_XYZE(i) mcp4728_values[i] = 0.01 * pct[i] * (DAC_STEPPER_MAX);
mcp4728_fastWrite();
}
/**
* FastWrite input register values - All DAC ouput update. refer to DATASHEET 5.6.1
* DAC Input and PowerDown bits update.
* No EEPROM update
*/
uint8_t mcp4728_fastWrite() {
Wire.beginTransmission(DAC_DEV_ADDRESS);
for (uint8_t channel = 0; channel < COUNT(channel); channel++) {
Wire.write(highByte(mcp4728_values[channel]));
Wire.write(lowByte(mcp4728_values[channel]));
}
return Wire.endTransmission();
}
/**
* Common function for simple general commands
*/
uint8_t mcp4728_simpleCommand(byte simpleCommand) {
Wire.beginTransmission(GENERALCALL);
Wire.write(simpleCommand);
return Wire.endTransmission();
}
#endif // DAC_STEPPER_CURRENT