klipper-dgus/klippy/extras/tmc_uart.py

248 lines
11 KiB
Python

# Helper code for communicating with TMC stepper drivers via UART
#
# Copyright (C) 2018-2019 Kevin O'Connor <kevin@koconnor.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
import logging
######################################################################
# TMC uart analog mux support
######################################################################
class MCU_analog_mux:
def __init__(self, mcu, cmd_queue, select_pins_desc):
self.mcu = mcu
self.cmd_queue = cmd_queue
ppins = mcu.get_printer().lookup_object("pins")
select_pin_params = [ppins.lookup_pin(spd, can_invert=True)
for spd in select_pins_desc.split(',')]
self.oids = [self.mcu.create_oid() for pp in select_pin_params]
self.pins = [pp['pin'] for pp in select_pin_params]
self.pin_values = tuple([-1 for pp in select_pin_params])
for oid, pin in zip(self.oids, self.pins):
self.mcu.add_config_cmd("config_digital_out oid=%d pin=%s"
" value=0 default_value=0 max_duration=0"
% (oid, pin))
self.update_pin_cmd = None
self.mcu.register_config_callback(self.build_config)
def build_config(self):
self.update_pin_cmd = self.mcu.lookup_command(
"update_digital_out oid=%c value=%c", cq=self.cmd_queue)
def get_instance_id(self, select_pins_desc):
ppins = self.mcu.get_printer().lookup_object("pins")
select_pin_params = [ppins.parse_pin(spd, can_invert=True)
for spd in select_pins_desc.split(',')]
for pin_params in select_pin_params:
if pin_params['chip'] != self.mcu:
raise self.mcu.get_printer().config_error(
"TMC mux pins must be on the same mcu")
pins = [pp['pin'] for pp in select_pin_params]
if pins != self.pins:
raise self.mcu.get_printer().config_error(
"All TMC mux instances must use identical pins")
return tuple([not pp['invert'] for pp in select_pin_params])
def activate(self, instance_id):
for oid, old, new in zip(self.oids, self.pin_values, instance_id):
if old != new:
self.update_pin_cmd.send([oid, new])
self.pin_values = instance_id
######################################################################
# TMC uart communication
######################################################################
# Share mutexes so only one active tmc_uart command on a single mcu at
# a time. This helps limit cpu usage on slower micro-controllers.
class PrinterTMCUartMutexes:
def __init__(self):
self.mcu_to_mutex = {}
def lookup_tmc_uart_mutex(mcu):
printer = mcu.get_printer()
pmutexes = printer.lookup_object('tmc_uart', None)
if pmutexes is None:
pmutexes = PrinterTMCUartMutexes()
printer.add_object('tmc_uart', pmutexes)
mutex = pmutexes.mcu_to_mutex.get(mcu)
if mutex is None:
mutex = printer.get_reactor().mutex()
pmutexes.mcu_to_mutex[mcu] = mutex
return mutex
TMC_BAUD_RATE = 9000
# Code for sending messages on a TMC uart
class MCU_TMC_uart_bitbang:
def __init__(self, rx_pin_params, tx_pin_params, select_pins_desc):
self.mcu = rx_pin_params['chip']
self.mutex = lookup_tmc_uart_mutex(self.mcu)
self.pullup = rx_pin_params['pullup']
self.rx_pin = rx_pin_params['pin']
self.tx_pin = tx_pin_params['pin']
self.oid = self.mcu.create_oid()
self.cmd_queue = self.mcu.alloc_command_queue()
self.analog_mux = None
if select_pins_desc is not None:
self.analog_mux = MCU_analog_mux(self.mcu, self.cmd_queue,
select_pins_desc)
self.instances = {}
self.tmcuart_send_cmd = None
self.mcu.register_config_callback(self.build_config)
def build_config(self):
bit_ticks = self.mcu.seconds_to_clock(1. / TMC_BAUD_RATE)
self.mcu.add_config_cmd(
"config_tmcuart oid=%d rx_pin=%s pull_up=%d tx_pin=%s bit_time=%d"
% (self.oid, self.rx_pin, self.pullup, self.tx_pin, bit_ticks))
self.tmcuart_send_cmd = self.mcu.lookup_query_command(
"tmcuart_send oid=%c write=%*s read=%c",
"tmcuart_response oid=%c read=%*s", oid=self.oid,
cq=self.cmd_queue, is_async=True)
def register_instance(self, rx_pin_params, tx_pin_params,
select_pins_desc, addr):
if (rx_pin_params['pin'] != self.rx_pin
or tx_pin_params['pin'] != self.tx_pin
or (select_pins_desc is None) != (self.analog_mux is None)):
raise self.mcu.get_printer().config_error(
"Shared TMC uarts must use the same pins")
instance_id = None
if self.analog_mux is not None:
instance_id = self.analog_mux.get_instance_id(select_pins_desc)
if (instance_id, addr) in self.instances:
raise self.mcu.get_printer().config_error(
"Shared TMC uarts need unique address or select_pins polarity")
self.instances[(instance_id, addr)] = True
return instance_id
def _calc_crc8(self, data):
# Generate a CRC8-ATM value for a bytearray
crc = 0
for b in data:
for i in range(8):
if (crc >> 7) ^ (b & 0x01):
crc = (crc << 1) ^ 0x07
else:
crc = (crc << 1)
crc &= 0xff
b >>= 1
return crc
def _add_serial_bits(self, data):
# Add serial start and stop bits to a message in a bytearray
out = 0
pos = 0
for d in data:
b = (d << 1) | 0x200
out |= (b << pos)
pos += 10
res = bytearray()
for i in range((pos+7)//8):
res.append((out >> (i*8)) & 0xff)
return res
def _encode_read(self, sync, addr, reg):
# Generate a uart read register message
msg = bytearray([sync, addr, reg])
msg.append(self._calc_crc8(msg))
return self._add_serial_bits(msg)
def _encode_write(self, sync, addr, reg, val):
# Generate a uart write register message
msg = bytearray([sync, addr, reg, (val >> 24) & 0xff,
(val >> 16) & 0xff, (val >> 8) & 0xff, val & 0xff])
msg.append(self._calc_crc8(msg))
return self._add_serial_bits(msg)
def _decode_read(self, reg, data):
# Extract a uart read response message
if len(data) != 10:
return None
# Convert data into a long integer for easy manipulation
mval = pos = 0
for d in bytearray(data):
mval |= d << pos
pos += 8
# Extract register value
val = ((((mval >> 31) & 0xff) << 24) | (((mval >> 41) & 0xff) << 16)
| (((mval >> 51) & 0xff) << 8) | ((mval >> 61) & 0xff))
# Verify start/stop bits and crc
encoded_data = self._encode_write(0x05, 0xff, reg, val)
if data != encoded_data:
return None
return val
def reg_read(self, instance_id, addr, reg):
if self.analog_mux is not None:
self.analog_mux.activate(instance_id)
msg = self._encode_read(0xf5, addr, reg)
params = self.tmcuart_send_cmd.send([self.oid, msg, 10])
return self._decode_read(reg, params['read'])
def reg_write(self, instance_id, addr, reg, val, print_time=None):
minclock = 0
if print_time is not None:
minclock = self.mcu.print_time_to_clock(print_time)
if self.analog_mux is not None:
self.analog_mux.activate(instance_id)
msg = self._encode_write(0xf5, addr, reg | 0x80, val)
self.tmcuart_send_cmd.send([self.oid, msg, 0], minclock=minclock)
# Lookup a (possibly shared) tmc uart
def lookup_tmc_uart_bitbang(config, max_addr):
ppins = config.get_printer().lookup_object("pins")
rx_pin_params = ppins.lookup_pin(
config.get('uart_pin'), can_pullup=True, share_type="tmc_uart_rx")
tx_pin_desc = config.get('tx_pin', None)
if tx_pin_desc is None:
tx_pin_params = rx_pin_params
else:
tx_pin_params = ppins.lookup_pin(tx_pin_desc, share_type="tmc_uart_tx")
if rx_pin_params['chip'] is not tx_pin_params['chip']:
raise ppins.error("TMC uart rx and tx pins must be on the same mcu")
select_pins_desc = config.get('select_pins', None)
addr = config.getint('uart_address', 0, minval=0, maxval=max_addr)
mcu_uart = rx_pin_params.get('class')
if mcu_uart is None:
mcu_uart = MCU_TMC_uart_bitbang(rx_pin_params, tx_pin_params,
select_pins_desc)
rx_pin_params['class'] = mcu_uart
instance_id = mcu_uart.register_instance(rx_pin_params, tx_pin_params,
select_pins_desc, addr)
return instance_id, addr, mcu_uart
# Helper code for communicating via TMC uart
class MCU_TMC_uart:
def __init__(self, config, name_to_reg, fields, max_addr=0):
self.printer = config.get_printer()
self.name = config.get_name().split()[-1]
self.name_to_reg = name_to_reg
self.fields = fields
self.ifcnt = None
self.instance_id, self.addr, self.mcu_uart = lookup_tmc_uart_bitbang(
config, max_addr)
self.mutex = self.mcu_uart.mutex
def get_fields(self):
return self.fields
def _do_get_register(self, reg_name):
reg = self.name_to_reg[reg_name]
if self.printer.get_start_args().get('debugoutput') is not None:
return 0
for retry in range(5):
val = self.mcu_uart.reg_read(self.instance_id, self.addr, reg)
if val is not None:
return val
raise self.printer.command_error(
"Unable to read tmc uart '%s' register %s" % (self.name, reg_name))
def get_register(self, reg_name):
with self.mutex:
return self._do_get_register(reg_name)
def set_register(self, reg_name, val, print_time=None):
reg = self.name_to_reg[reg_name]
if self.printer.get_start_args().get('debugoutput') is not None:
return
with self.mutex:
for retry in range(5):
ifcnt = self.ifcnt
if ifcnt is None:
self.ifcnt = ifcnt = self._do_get_register("IFCNT")
self.mcu_uart.reg_write(self.instance_id, self.addr, reg, val,
print_time)
self.ifcnt = self._do_get_register("IFCNT")
if self.ifcnt == (ifcnt + 1) & 0xff:
return
raise self.printer.command_error(
"Unable to write tmc uart '%s' register %s" % (self.name, reg_name))