tmc2130: Add initial support for TMC2130 stepper motor drivers

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

2 files changed, 108 insertions, 0 deletions

diff --git a/config/example-extras.cfg b/config/example-extras.cfg
index 5da4293a..82fdfd9d 100644
--- a/config/example-extras.cfg
+++ b/config/example-extras.cfg
@@ -402,6 +402,44 @@
 #   default is to not scale the 'channel_x' parameters.
 
 
+# Configure a TMC2130 stepper motor driver (one may define any number
+# of sections with a "tmc2130" prefix).
+#[tmc2130 my_name]
+#cs_pin:
+#   The pin corresponding to the TMC2130 chip select line. This pin
+#   will be set to low at the start of SPI messages and raised to high
+#   after the message completes. This parameter must be provided.
+#microsteps:
+#   The number of microsteps to configure the driver to use. Valid
+#   values are 1, 2, 4, 8, 16, 32, 64, 128, 256. This parameter must
+#   be provided.
+#interpolate: True
+#   If true, enable TMC2130 step interpolation (the driver will
+#   interally step at a rate of 256 micro-steps). The default is True.
+#run_current:
+#   The amount of current (in amps) to configure the driver to use
+#   during stepper movement. This parameter must be provided.
+#hold_current:
+#   The amount of current (in amps) to configure the driver to use
+#   when the stepper is not moving. The default is to use the same
+#   value as run_current.
+#sense_resistor: 0.110
+#   The resistance (in ohms) of the motor sense resistor. The default
+#   is 0.110 ohms.
+#stealthchop: False
+#   Enable "stealthChop" mode. The default is False.
+#driver_IHOLDDELAY: 8
+#driver_TPOWERDOWN: 0
+#driver_BLANK_TIME_SELECT: 1
+#driver_TOFF: 1
+#driver_HEND: 7
+#driver_HSTRT: 0
+#   Set the given register during the configuration of the TMC2130
+#   chip. This may be used to set custom motor parameters. The
+#   defaults for each parameter are next to the parameter name in the
+#   above list.
+
+
 # Homing override. One may use this mechanism to run a series of
 # g-code commands in place of a G28 found in the normal g-code input.
 # This may be useful on printers that require a specific procedure to
diff --git a/klippy/extras/tmc2130.py b/klippy/extras/tmc2130.py
new file mode 100644
index 00000000..72d1faf1
--- /dev/null
+++ b/klippy/extras/tmc2130.py
@@ -0,0 +1,70 @@
+# TMC2130 configuration
+#
+# Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+import math
+
+class tmc2130:
+    def __init__(self, config):
+        printer = config.get_printer()
+        # pin setup
+        ppins = printer.lookup_object("pins")
+        cs_pin = config.get('cs_pin')
+        cs_pin_params = ppins.lookup_pin('digital_out', cs_pin)
+        if cs_pin_params['invert']:
+            raise pins.error("tmc2130 can not invert pin")
+        self.mcu = cs_pin_params['chip']
+        pin = cs_pin_params['pin']
+        self.oid = self.mcu.create_oid()
+        self.mcu.add_config_cmd(
+            "config_spi oid=%d bus=%d pin=%s mode=%d rate=%d shutdown_msg=" % (
+                self.oid, 0, cs_pin_params['pin'], 3, 3600000))
+        run_current = config.getfloat('run_current', above=0., maxval=2.)
+        hold_current = config.getfloat('hold_current', run_current,
+                                       above=0., maxval=2.)
+        sense_resistor = config.getfloat('sense_resistor', 0.110, above=0.)
+        steps = {'256': 0, '128': 1, '64': 2, '32': 3, '16': 4,
+                 '8': 5, '4': 6, '2': 7, '1': 8}
+        microsteps = config.getchoice('microsteps', steps)
+        interpolate = config.getboolean('interpolate', True)
+        stealthchop = config.getboolean('stealthchop', False)
+        iholddelay = config.getint('driver_IHOLDDELAY', 8, minval=0, maxval=15)
+        tpowerdown = config.getint('driver_TPOWERDOWN', 0, minval=0, maxval=255)
+        blank_time_select = config.getint('driver_BLANK_TIME_SELECT', 1,
+                                          minval=0, maxval=3)
+        toff = config.getint('driver_TOFF', 1, minval=1, maxval=15)
+        hend = config.getint('driver_HEND', 7, minval=0, maxval=15)
+        hstrt = config.getint('driver_HSTRT', 0, minval=0, maxval=7)
+        # calculate current
+        vsense = False
+        irun = self.current_bits(run_current, sense_resistor, vsense)
+        ihold = self.current_bits(hold_current, sense_resistor, vsense)
+        if irun < 16 and ihold < 16:
+            vsense = True
+            irun = self.current_bits(run_current, sense_resistor, vsense)
+            ihold = self.current_bits(hold_current, sense_resistor, vsense)
+        # configure GCONF
+        self.add_config_cmd(0x00, stealthchop << 2)
+        # configure CHOPCONF
+        self.add_config_cmd(
+            0x6c, toff | (hstrt << 4) | (hend << 7) | (blank_time_select << 15)
+            | (vsense << 17) | (microsteps << 24) | (interpolate << 28))
+        # configure IHOLD_IRUN
+        self.add_config_cmd(0x10, ihold | (irun << 8) | (iholddelay << 16))
+        # configure TPOWERDOWN
+        self.add_config_cmd(0x11, tpowerdown)
+    def add_config_cmd(self, addr, val):
+        self.mcu.add_config_cmd("spi_send oid=%d data=%02x%08x" % (
+            self.oid, (addr | 0x80) & 0xff, val & 0xffffffff), is_init=True)
+    def current_bits(self, current, sense_resistor, vsense_on):
+        sense_resistor += 0.020
+        vsense = 0.32
+        if vsense_on:
+            vsense = 0.18
+        cs = int(32. * current * sense_resistor * math.sqrt(2.) / vsense
+                 - 1. + .5)
+        return max(0, min(31, cs))
+
+def load_config_prefix(config):
+    return tmc2130(config)