Marlin_Firmware/Marlin/src/feature/digipot/digipot_mcp4018.cpp
2020-12-17 17:22:59 -06:00

105 lines
3.9 KiB
C++

/**
* Marlin 3D Printer Firmware
* Copyright (c) 2020 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 <https://www.gnu.org/licenses/>.
*
*/
#include "../../inc/MarlinConfig.h"
#if ENABLED(DIGIPOT_MCP4018)
#include "digipot.h"
#include <Stream.h>
#include <SlowSoftI2CMaster.h> // https://github.com/felias-fogg/SlowSoftI2CMaster
// Settings for the I2C based DIGIPOT (MCP4018) based on WT150
#define DIGIPOT_A4988_Rsx 0.250
#define DIGIPOT_A4988_Vrefmax 1.666
#define DIGIPOT_MCP4018_MAX_VALUE 127
#define DIGIPOT_A4988_Itripmax(Vref) ((Vref) / (8.0 * DIGIPOT_A4988_Rsx))
#define DIGIPOT_A4988_FACTOR ((DIGIPOT_MCP4018_MAX_VALUE) / DIGIPOT_A4988_Itripmax(DIGIPOT_A4988_Vrefmax))
#define DIGIPOT_A4988_MAX_CURRENT 2.0
static byte current_to_wiper(const float current) {
const int16_t value = TERN(DIGIPOT_USE_RAW_VALUES, current, CEIL(current * DIGIPOT_A4988_FACTOR));
return byte(constrain(value, 0, DIGIPOT_MCP4018_MAX_VALUE));
}
static SlowSoftI2CMaster pots[DIGIPOT_I2C_NUM_CHANNELS] = {
SlowSoftI2CMaster(DIGIPOTS_I2C_SDA_X, DIGIPOTS_I2C_SCL, ENABLED(DIGIPOT_ENABLE_I2C_PULLUPS))
#if DIGIPOT_I2C_NUM_CHANNELS > 1
, SlowSoftI2CMaster(DIGIPOTS_I2C_SDA_Y, DIGIPOTS_I2C_SCL, ENABLED(DIGIPOT_ENABLE_I2C_PULLUPS))
#if DIGIPOT_I2C_NUM_CHANNELS > 2
, SlowSoftI2CMaster(DIGIPOTS_I2C_SDA_Z, DIGIPOTS_I2C_SCL, ENABLED(DIGIPOT_ENABLE_I2C_PULLUPS))
#if DIGIPOT_I2C_NUM_CHANNELS > 3
, SlowSoftI2CMaster(DIGIPOTS_I2C_SDA_E0, DIGIPOTS_I2C_SCL, ENABLED(DIGIPOT_ENABLE_I2C_PULLUPS))
#if DIGIPOT_I2C_NUM_CHANNELS > 4
, SlowSoftI2CMaster(DIGIPOTS_I2C_SDA_E1, DIGIPOTS_I2C_SCL, ENABLED(DIGIPOT_ENABLE_I2C_PULLUPS))
#if DIGIPOT_I2C_NUM_CHANNELS > 5
, SlowSoftI2CMaster(DIGIPOTS_I2C_SDA_E2, DIGIPOTS_I2C_SCL, ENABLED(DIGIPOT_ENABLE_I2C_PULLUPS))
#if DIGIPOT_I2C_NUM_CHANNELS > 6
, SlowSoftI2CMaster(DIGIPOTS_I2C_SDA_E3, DIGIPOTS_I2C_SCL, ENABLED(DIGIPOT_ENABLE_I2C_PULLUPS))
#if DIGIPOT_I2C_NUM_CHANNELS > 7
, SlowSoftI2CMaster(DIGIPOTS_I2C_SDA_E4, DIGIPOTS_I2C_SCL, ENABLED(DIGIPOT_ENABLE_I2C_PULLUPS))
#endif
#endif
#endif
#endif
#endif
#endif
#endif
};
static void digipot_i2c_send(const uint8_t channel, const byte v) {
if (WITHIN(channel, 0, DIGIPOT_I2C_NUM_CHANNELS - 1)) {
pots[channel].i2c_start(((DIGIPOT_I2C_ADDRESS_A) << 1) | I2C_WRITE);
pots[channel].i2c_write(v);
pots[channel].i2c_stop();
}
}
// This is for the MCP4018 I2C based digipot
void DigipotI2C::set_current(const uint8_t channel, const float current) {
const float ival = _MIN(_MAX(current, 0), float(DIGIPOT_MCP4018_MAX_VALUE));
digipot_i2c_send(channel, current_to_wiper(ival));
}
void DigipotI2C::init() {
LOOP_L_N(i, DIGIPOT_I2C_NUM_CHANNELS) pots[i].i2c_init();
// Init currents according to Configuration_adv.h
static const float digipot_motor_current[] PROGMEM =
#if ENABLED(DIGIPOT_USE_RAW_VALUES)
DIGIPOT_MOTOR_CURRENT
#else
DIGIPOT_I2C_MOTOR_CURRENTS
#endif
;
LOOP_L_N(i, COUNT(digipot_motor_current))
set_current(i, pgm_read_float(&digipot_motor_current[i]));
}
DigipotI2C digipot_i2c;
#endif // DIGIPOT_MCP4018