40,16 → 40,21 |
DISTANCE = 50 |
|
class axis: |
def __init__(self, SPI_handler, Direction, StepsPerUnit): |
def __init__(self, SPI_handler, Direction, StepsPerUnit, MaxSpeed): |
' One axis of robot ' |
self.spi = SPI_handler |
self.Dir = Direction |
self.SPU = StepsPerUnit |
self.maxseed = MaxSpeed |
self.Reset() |
self.Initialize() |
|
def Reset(self): |
' Reset Axis and set default parameters for H-bridge ' |
'Reset the Axis' |
self.spi.xfer([0xC0]) # reset |
|
def Initialize(self): |
'set default parameters for H-bridge ' |
# self.spi.xfer( 0x14) # Stall Treshold setup |
# self.spi.xfer( 0xFF) |
# self.spi.xfer( 0x13) # Over Current Treshold setup |
64,26 → 69,33 |
self.spi.xfer([0x00]) |
self.spi.xfer([0x10]) |
self.spi.xfer([0x0A]) # KVAL_RUN |
self.spi.xfer([0xFF]) |
self.spi.xfer([0x50]) |
self.spi.xfer([0x0B]) # KVAL_ACC |
self.spi.xfer([0xFF]) |
self.spi.xfer([0x50]) |
self.spi.xfer([0x0C]) # KVAL_DEC |
self.spi.xfer([0xFF]) |
self.spi.xfer([0x18]) # CONFIG |
self.spi.xfer([0b00111000]) |
self.spi.xfer([0b00000000]) |
self.spi.xfer([0x05]) |
# self.spi.xfer([0x18]) # CONFIG |
# self.spi.xfer([0b00111000]) |
# self.spi.xfer([0b00000000]) |
|
def MaxSpeed(self, speed): |
' Setup of maximum speed ' |
self.spi.xfer([0x07]) # Max Speed setup |
self.spi.xfer([0x00]) |
self.spi.xfer([speed]) |
'Setup of maximum speed in steps/s' |
speed_value = int(speed / 15.25) |
if (speed_value == 0): |
speed_value = 1 |
print hex(speed_value) |
|
data = [(speed_value >> i & 0xff) for i in (16,8,0)] |
self.spi.xfer([data[0]]) # Max Speed setup |
self.spi.xfer([data[1]]) |
self.spi.xfer([data[2]]) |
return (speed_value * 15.25) |
|
def ReleaseSW(self): |
' Go away from Limit Switch ' |
while self.ReadStatusBit(2) == 1: # is Limit Switch ON ? |
self.spi.xfer([0x92 | (~self.Dir & 1)]) # release SW |
while self.IsBusy(): |
while self.GetStatus()['BUSY']: |
pass |
self.MoveWait(10) # move 10 units away |
|
90,15 → 102,37 |
def GoZero(self, speed): |
' Go to Zero position ' |
self.ReleaseSW() |
|
self.spi.xfer([0x82 | (self.Dir & 1)]) # Go to Zero |
self.spi.xfer([0x00]) |
self.spi.xfer([speed]) |
while self.IsBusy(): |
while self.GetStatus()['BUSY']: |
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 |
self.spi.xfer([0x39]) # Gotparam command on status register |
data = self.spi.readbytes(1) |
data = data + self.spi.readbytes(1) |
|
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 Move(self, units): |
' Move some distance units from current position ' |
steps = units * self.SPU # translate units to steps |
111,43 → 145,38 |
self.spi.xfer([(steps >> 8) & 0xFF]) |
self.spi.xfer([steps & 0xFF]) |
|
def Run(self, direction, speed): |
speed_value = int(speed / 0.015) |
print hex(speed_value) |
|
data = [0b01010000 + direction] |
data = data +[(speed_value >> i & 0xff) for i in (16,8,0)] |
self.spi.xfer([data[0]]) # Max Speed setup |
self.spi.xfer([data[1]]) |
self.spi.xfer([data[2]]) |
self.spi.xfer([data[3]]) |
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.IsBusy(): |
while self.GetStatus()['BUSY']: |
pass |
time.sleep(0.8) |
|
def Float(self): |
def Float(self, hard = False): |
' switch H-bridge to High impedance state ' |
self.spi.xfer([0xA0]) |
|
def ReadStatusBit(self, bit): |
' Report given status bit ' |
self.spi.xfer([0x39]) # Get status command |
data = self.spi.readbytes(1) # 1st byte |
data = data + (self.spi.readbytes(1)) # 1st byte |
print data |
if bit > 7: # extract requested bit |
OutputBit = (data[0] >> (bit - 8)) & 1 |
if (hard == False): |
self.spi.xfer([0xA0]) |
else: |
OutputBit = (data[1] >> bit) & 1 |
return OutputBit |
self.spi.xfer([0xA8]) |
|
|
|
def IsBusy(self): |
""" Return True if tehre are motion """ |
if self.ReadStatusBit(1) == 1: |
return False |
else: |
return True |
|
# End Class axis -------------------------------------------------- |
|
print "Stepper motor control test started. \r\n" |
print "Max motor speed: %d " % SPEED |
print "Distance to run: %d " % DISTANCE |
print "Max motor speed: %f " % SPEED |
print "Distance to run: %f " % DISTANCE |
|
try: |
print "SPI configuration.." |
157,15 → 186,19 |
spi.lsbfirst = False |
spi.bits_per_word = 8 |
spi.cshigh = False |
spi.max_speed_hz = 100000 |
#spi.SPI_config(spi.I2CSPI_MSB_FIRST| spi.I2CSPI_MODE_CLK_IDLE_HIGH_DATA_EDGE_TRAILING| spi.I2CSPI_CLK_461kHz) |
time.sleep(1) |
|
print "Axis inicialization" |
X = axis(spi, 0, 641) # set Number of Steps per axis Unit and set Direction of Rotation |
X.MaxSpeed(SPEED) # set maximal motor speed |
X = axis(spi, 0, 641, MaxSpeed = SPEED) # set Number of Steps per axis Unit and set Direction of Rotation |
|
print X.MaxSpeed(SPEED) # set maximal motor speed |
|
print X.Run(1, 200.456431) |
time.sleep(10) |
''' |
print "Axis is running" |
|
for i in range(5): |
print i |
X.MoveWait(DISTANCE) # move forward and wait for motor stop |
174,8 → 207,8 |
X.MoveWait(-DISTANCE) # move backward and wait for motor stop |
print "Changing direction of rotation.." |
time.sleep(1.1) |
X.Float() # release power |
''' |
X.Float(hard=False) # release power |
|
|
finally: |
print "stop" |