#!/usr/bin/python
# -------------------------------------------
# HBSTEP01B Stepper Motor control test code
# -------------------------------------------
#
# Program uses MLAB Python modules library from https://github.com/MLAB-project/pymlab
#uncomment for debbug purposes
#import logging
#logging.basicConfig(level=logging.DEBUG)
import sys
import time
from pymlab import config
import pylirc # infrared receiver binding
#### Script Arguments ###############################################
if len(sys.argv) == 2:
SPEED = eval(sys.argv[1])
else:
sys.stderr.write("Invalid number of arguments.\n")
sys.stderr.write("Usage: %s BASE_SPEED (in steps/s)\n" % (sys.argv[0], ))
sys.exit(1)
# Begin of Class Axis --------------------------------------------------
class axis:
def __init__(self, SPI_CS, Direction, StepsPerUnit, MaxSpeed):
' One axis of robot '
self.CS = SPI_CS
self.Dir = Direction
self.SPU = StepsPerUnit
self.maxspeed = MaxSpeed
self.L6470_ABS_POS =0x01
self.L6470_EL_POS =0x02
self.L6470_MARK =0x03
self.L6470_SPEED =0x04
self.L6470_ACC =0x05
self.L6470_DEC =0x06
self.L6470_MAX_SPEED =0x07
self.L6470_MIN_SPEED =0x08
self.L6470_FS_SPD =0x15
self.L6470_KVAL_HOLD =0x09
self.L6470_KVAL_RUN =0x0A
self.L6470_KVAL_ACC =0x0B
self.L6470_KVAL_DEC =0x0C
self.L6470_INT_SPEED =0x0D
self.L6470_ST_SLP =0x0E
self.L6470_FN_SLP_ACC =0x0F
self.L6470_FN_SLP_DEC =0x10
self.L6470_K_THERM =0x11
self.L6470_ADC_OUT =0x12
self.L6470_OCD_TH =0x13
self.L6470_STALL_TH =0x14
self.L6470_STEP_MODE =0x16
self.L6470_ALARM_EN =0x17
self.L6470_CONFIG =0x18
self.L6470_STATUS =0x19
self.Reset()
self.Initialize()
self.MaxSpeed(self.maxspeed)
def Reset(self):
'Reset the Axis'
spi.SPI_write_byte(self.CS, 0xC0) # reset
def Initialize(self):
'set default parameters for H-bridge '
# spi.SPI_write_byte(self.CS, 0x14) # Stall Treshold setup
# spi.SPI_write_byte(self.CS, 0xFF)
# spi.SPI_write_byte(self.CS, 0x13) # Over Current Treshold setup
# spi.SPI_write_byte(self.CS, 0xFF)
spi.SPI_write_byte(self.CS, 0x15) # Full Step speed
spi.SPI_write_byte(self.CS, 0xFF)
spi.SPI_write_byte(self.CS, 0xFF)
spi.SPI_write_byte(self.CS, 0x05) # ACC
spi.SPI_write_byte(self.CS, 0x00)
spi.SPI_write_byte(self.CS, 0x10)
spi.SPI_write_byte(self.CS, 0x06) # DEC
spi.SPI_write_byte(self.CS, 0x00)
spi.SPI_write_byte(self.CS, 0x10)
spi.SPI_write_byte(self.CS, self.L6470_KVAL_RUN) # KVAL_RUN
spi.SPI_write_byte(self.CS, 0x18)
spi.SPI_write_byte(self.CS, self.L6470_KVAL_ACC) # KVAL_ACC
spi.SPI_write_byte(self.CS, 0x18)
spi.SPI_write_byte(self.CS, self.L6470_KVAL_DEC) # KVAL_DEC
spi.SPI_write_byte(self.CS, 0x18)
spi.SPI_write_byte(self.CS, 0x18) # CONFIG
spi.SPI_write_byte(self.CS, 0b00101110) # spolecny byte pro obe konfigurace
spi.SPI_write_byte(self.CS, 0b10000000) # konfigurace pro interni oscilator
# spi.SPI_write_byte(self.CS, 0b10000110) # konfigurace s externim oscilatorem
self.MaxSpeed(self.maxspeed)
def setKVAL(self, hold = 0.5, run = 0.5, acc = 0.5, dec = 0.5):
""" The available range is from 0 to 0.996 x VS with a resolution of 0.004 x VS """
def setOverCurrentTH(self, hold = 0.5, run = 0.5, acc = 0.5, dec = 0.5):
""" The available range is from 375 mA to 6 A, in steps of 375 mA """
def MaxSpeed(self, speed):
'Setup of maximum speed in steps/s. The available range is from 15.25 to 15610 step/s with a resolution of 15.25 step/s.'
speed_value = int(speed / 15.25)
if (speed_value <= 0):
speed_value = 1
elif (speed_value >= 1023):
speed_value = 1023
data = [(speed_value >> i & 0xff) for i in (8,0)]
spi.SPI_write_byte(self.CS, self.L6470_MAX_SPEED) # Max Speed setup
spi.SPI_write_byte(self.CS, data[0])
spi.SPI_write_byte(self.CS, data[1])
return (speed_value * 15.25)
def ReleaseSW(self):
' Go away from Limit Switch '
while self.ReadStatusBit(2) == 1: # is Limit Switch ON ?
spi.SPI_write_byte(self.CS, 0x92 | (~self.Dir & 1)) # release SW
while self.IsBusy():
pass
self.MoveWait(10) # move 10 units away
def GoZero(self, speed):
' Go to Zero position '
self.ReleaseSW()
spi.SPI_write_byte(self.CS, 0x82 | (self.Dir & 1)) # Go to Zero
spi.SPI_write_byte(self.CS, 0x00)
spi.SPI_write_byte(self.CS, speed)
while self.IsBusy():
pass
time.sleep(0.3)
self.ReleaseSW()
def GetStatus(self):
#self.spi.xfer([0b11010000]) # Get status command from datasheet - does not work for uknown rasons
spi.SPI_write_byte(self.CS, 0x39) # Gotparam command on status register
spi.SPI_write_byte(self.CS, 0x00)
data = [spi.SPI_read_byte()]
spi.SPI_write_byte(self.CS, 0x00)
data = data + [spi.SPI_read_byte()]
status = dict([('SCK_MOD',data[0] & 0x80 == 0x80), #The SCK_MOD bit is an active high flag indicating that the device is working in Step-clock mode. In this case the step-clock signal should be provided through the STCK input pin. The DIR bit indicates the current motor direction
('STEP_LOSS_B',data[0] & 0x40 == 0x40),
('STEP_LOSS_A',data[0] & 0x20 == 0x20),
('OCD',data[0] & 0x10 == 0x10),
('TH_SD',data[0] & 0x08 == 0x08),
('TH_WRN',data[0] & 0x04 == 0x04),
('UVLO',data[0] & 0x02 == 0x02),
('WRONG_CMD',data[0] & 0x01 == 0x01), #The NOTPERF_CMD and WRONG_CMD flags are active high and indicate, respectively, that the command received by SPI cannot be performed or does not exist at all.
('NOTPERF_CMD',data[1] & 0x80 == 0x80),
('MOT_STATUS',data[1] & 0x60),
('DIR',data[1] & 0x10 == 0x10),
('SW_EVN',data[1] & 0x08 == 0x08),
('SW_F',data[1] & 0x04 == 0x04), #The SW_F flag reports the SW input status (low for open and high for closed).
('BUSY',data[1] & 0x02 != 0x02),
('HIZ',data[1] & 0x01 == 0x01)])
return status
def GetACC(self):
# self.spi.xfer([0x29]) # Gotparam command on status register
spi.SPI_write_byte(self.CS, self.L6470_ACC + 0x20) # TODO check register read address seting
spi.SPI_write_byte(self.CS, 0x00)
data = spi.SPI_read_byte()
spi.SPI_write_byte(self.CS, 0x00)
data = data + [spi.SPI_read_byte()]
print data # return speed in real units
def Move(self, units):
' Move some distance units from current position '
steps = units * self.SPU # translate units to steps
if steps > 0: # look for direction
spi.SPI_write_byte(self.CS, 0x40 | (~self.Dir & 1))
else:
spi.SPI_write_byte(self.CS, 0x40 | (self.Dir & 1))
steps = int(abs(steps))
spi.SPI_write_byte(self.CS, (steps >> 16) & 0xFF)
spi.SPI_write_byte(self.CS, (steps >> 8) & 0xFF)
spi.SPI_write_byte(self.CS, steps & 0xFF)
def Run(self, direction, speed):
speed_value = int(speed / 0.015)
command = 0b01010000 + int(direction)
data = [(speed_value >> i & 0xff) for i in (16,8,0)]
spi.SPI_write_byte(self.CS, command) # Max Speed setup
spi.SPI_write_byte(self.CS, data[0])
spi.SPI_write_byte(self.CS, data[1])
spi.SPI_write_byte(self.CS, data[2])
return (speed_value * 0.015)
def MoveWait(self, units):
' Move some distance units from current position and wait for execution '
self.Move(units)
while self.GetStatus()['BUSY']:
time.sleep(0.1)
def Float(self, hard = False):
' switch H-bridge to High impedance state '
if (hard == False):
spi.SPI_write_byte(self.CS, 0xA0)
else:
spi.SPI_write_byte(self.CS, 0xA8)
# End Class axis --------------------------------------------------
print "Clock motor control script started. \r\n"
print "Requested speed is: %f steps/s" % SPEED
pylirc.init("pylirc", "/home/odroid/conf")
cfg = config.Config(
i2c = {
"port": 1,
},
bus = [
{
"name":"spi",
"type":"i2cspi",
"address": 0x2e,
},
],
)
cfg.initialize()
spi = cfg.get_device("spi")
spi.route()
try:
print "Configuring SPI.."
spi.SPI_config(spi.I2CSPI_MSB_FIRST| spi.I2CSPI_MODE_CLK_IDLE_HIGH_DATA_EDGE_TRAILING| spi.I2CSPI_CLK_461kHz)
time.sleep(0.1)
maximum_speed = 2 * SPEED
print "Configuring stepper motor.."
X = axis(spi.I2CSPI_SS0, 0, 1, MaxSpeed = maximum_speed) # set Number of Steps per axis Unit and set Direction of Rotation
print "Motor speed limit is: %f steps/s" % maximum_speed
running = False
print "Waiting for IR command.."
while True: # set maximal motor speed
key = pylirc.nextcode() ## preccessing the IR remote control commands.
if key == ['start']:
running = True
direction = True
requested_speed = SPEED
if key == ['faster']:
running = True
direction = True
requested_speed = SPEED * 1.2 # runnig the motor at 120% of the base motor speed
if key == ['slower']:
running = True
direction = True
requested_speed = SPEED * 0.8
if key == ['stop']:
running = False
time.sleep(0.1)
if running == True:
real_speed = X.Run(direction, requested_speed)
print "Motor running at: %f steps/s" % real_speed
else:
X.Float(hard=False) # release power
X.Reset()
X.Initialize()
print "Stopping the motor."
except KeyboardInterrupt:
print "stop"
X.Float(hard=False) # release power
sys.exit(0)
except Exception, e:
X.Float(hard=False) # release power
print >> sys.stderr, "Exception: %s" % str(e)
sys.exit(1)