Current control

Makefile

@@ -34,6 +34,7 @@ INCLUDES =                                        \
 # Hack: .c files are compiled as if they were c++.
 SRC_DIRS =          \
 	grbl            \
+    smoother        \
 
 # Compile all .c files in these directories, except ones on the exclude list.
 # These files get extra -Wno-* flags to reduce spam.
@@ -145,7 +146,7 @@ build/src/%.o : %.cpp
 default: build/$(PROJECT).hex build/$(PROJECT).bin
 
 build/$(PROJECT).elf: $(SRC_OBJECTS) $(CMSIS_OBJECTS) $(LINKER_SCRIPT)
-	$(LD) -mcpu=cortex-m3 -mthumb -T$(filter %.ld, $^) -o $@ $(filter %.o, $^) $(LIBS)
+	$(LD) -mcpu=cortex-m3 -mthumb -specs=nosys.specs -T$(filter %.ld, $^) -o $@ $(filter %.o, $^) $(LIBS)
 
 build/$(PROJECT).bin : build/$(PROJECT).elf
 	$(OBJCOPY) -O binary $^ $@
@@ -161,4 +162,4 @@ flash: build/$(PROJECT).hex
 clean:
 	$(call RM,build)
 
--include $(wildcard build/*.d build/cmsis/*.d)
+-include $(wildcard build/src/*.d build/cmsis/*.d)

grbl/config.h

@@ -696,22 +696,31 @@
 #define SPINDLE_PWM_PORT  PORTB
 #define SPINDLE_PWM_BIT	  3    // Uno Digital Pin 11
 
+#define CURRENT_I2C Driver_I2C1         // I2C driver for current control. Comment out to disable.
+#define CURRENT_MCP44XX_ADDR 0b0101100  // Address of MCP44XX
+#define CURRENT_WIPERS {0, 1, 6, 7};    // Wiper registers (X, Y, Z, A)
+#define CURRENT_FACTOR 113.33           // Convert amps to digipot value
+
 // Paste default settings definitions here.
-#define DEFAULT_X_STEPS_PER_MM 250.0
+#define DEFAULT_X_STEPS_PER_MM 158.0
-#define DEFAULT_Y_STEPS_PER_MM 250.0
+#define DEFAULT_Y_STEPS_PER_MM 158.0
-#define DEFAULT_Z_STEPS_PER_MM 250.0
+#define DEFAULT_Z_STEPS_PER_MM 158.0
-#define DEFAULT_X_MAX_RATE 500.0 // mm/min
+#define DEFAULT_X_MAX_RATE 30000 // mm/min
-#define DEFAULT_Y_MAX_RATE 500.0 // mm/min
+#define DEFAULT_Y_MAX_RATE 30000 // mm/min
 #define DEFAULT_Z_MAX_RATE 500.0 // mm/min
-#define DEFAULT_X_ACCELERATION (10.0*60*60) // 10*60*60 mm/min^2 = 10 mm/sec^2
+#define DEFAULT_X_ACCELERATION (5000.0*60*60) // 5000*60*60 mm/min^2 = 5000 mm/sec^2
-#define DEFAULT_Y_ACCELERATION (10.0*60*60) // 10*60*60 mm/min^2 = 10 mm/sec^2
+#define DEFAULT_Y_ACCELERATION (5000.0*60*60) // 5000*60*60 mm/min^2 = 5000 mm/sec^2
-#define DEFAULT_Z_ACCELERATION (10.0*60*60) // 10*60*60 mm/min^2 = 10 mm/sec^2
+#define DEFAULT_Z_ACCELERATION (5000.0*60*60) // 5000*60*60 mm/min^2 = 5000 mm/sec^2
+#define DEFAULT_X_CURRENT 0.4 // amps
+#define DEFAULT_Y_CURRENT 1.5 // amps
+#define DEFAULT_Z_CURRENT 0.0 // amps
+#define DEFAULT_A_CURRENT 0.0  // amps
 #define DEFAULT_X_MAX_TRAVEL 200.0 // mm
 #define DEFAULT_Y_MAX_TRAVEL 200.0 // mm
 #define DEFAULT_Z_MAX_TRAVEL 200.0 // mm
 #define DEFAULT_SPINDLE_RPM_MAX 1000.0 // rpm
 #define DEFAULT_SPINDLE_RPM_MIN 0.0 // rpm
-#define DEFAULT_STEP_PULSE_MICROSECONDS 10
+#define DEFAULT_STEP_PULSE_MICROSECONDS 1
 #define DEFAULT_STEPPING_INVERT_MASK 0
 #define DEFAULT_DIRECTION_INVERT_MASK 0
 #define DEFAULT_STEPPER_IDLE_LOCK_TIME 25 // msec (0-254, 255 keeps steppers enabled)

grbl/main.c

@@ -20,6 +20,7 @@
 */
 
 #include "grbl.h"
+#include "current_control.h"
 
 /*Holding space for dummy registers*/
 DummyReg DDRA;
@@ -89,6 +90,7 @@ int main(void)
   // Initialize system upon power-up.
   serial_init();   // Setup serial baud rate and interrupts
   settings_init(); // Load Grbl settings from EEPROM
+  current_init();  // Configure stepper driver current
   stepper_init();  // Configure stepper pins and interrupt timers
   system_init();   // Configure pinout pins and pin-change interrupt
 

lpc17xx/RTE_Device.h

@@ -249,7 +249,7 @@
 
 // <e> I2C1 (Inter-integrated Circuit Interface 1) [Driver_I2C1]
 // <i> Configuration settings for Driver_I2C1 in component ::Drivers:I2C
-#define RTE_I2C1                        0
+#define RTE_I2C1                        1
 
 //   <o> I2C1_SCL Pin <0=>P0_1 <1=>P0_20
 #define RTE_I2C1_SCL_PORT_ID            0

smoother/current_control.cpp

@@ -0,0 +1,63 @@
+// Current control
+//
+// Copyright 2017 Todd Fleming
+//
+// 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 THE
+// AUTHORS OR COPYRIGHT HOLDERS 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.
+
+#include "current_control.h"
+#include "grbl.h"
+#include "Driver_I2C.h"
+
+#ifdef CURRENT_I2C
+extern ARM_DRIVER_I2C CURRENT_I2C;
+static const uint8_t wiperRegs[] = CURRENT_WIPERS;
+#endif
+
+void current_init()
+{
+#ifdef CURRENT_I2C
+    CURRENT_I2C.Initialize(nullptr);
+    CURRENT_I2C.PowerControl(ARM_POWER_FULL);
+    CURRENT_I2C.Control(ARM_I2C_BUS_SPEED, ARM_I2C_BUS_SPEED_STANDARD);
+    CURRENT_I2C.Control(ARM_I2C_BUS_CLEAR, 0);
+
+    uint8_t init1[] = {0x40, 0xff};
+    uint8_t init2[] = {0xA0, 0xff};
+    CURRENT_I2C.MasterTransmit(CURRENT_MCP44XX_ADDR, init1, 2, false);
+    CURRENT_I2C.MasterTransmit(CURRENT_MCP44XX_ADDR, init2, 2, false);
+
+    set_current(0, DEFAULT_X_CURRENT);
+    set_current(1, DEFAULT_Y_CURRENT);
+    set_current(2, DEFAULT_Z_CURRENT);
+    set_current(3, DEFAULT_A_CURRENT);
+#endif
+}
+
+void set_current(uint8_t motor, float amps)
+{
+#if defined(CURRENT_I2C) && defined(CURRENT_MCP44XX_ADDR)
+    uint8_t command[] = {
+        uint8_t(wiperRegs[motor] << 4),
+        uint8_t(std::round(amps * CURRENT_FACTOR)),
+    };
+    CURRENT_I2C.MasterTransmit(CURRENT_MCP44XX_ADDR, command, sizeof(command), false);
+    while (CURRENT_I2C.GetStatus().busy)
+        ;
+#endif
+}

smoother/current_control.h

@@ -0,0 +1,26 @@
+// Current control
+//
+// Copyright 2017 Todd Fleming
+//
+// 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 THE
+// AUTHORS OR COPYRIGHT HOLDERS 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.
+
+#include <stdint.h>
+
+void current_init();
+void set_current(uint8_t motor, float amps);