Gpio.py File Reference

Laelaps Odroid GPIO control. More...

Go to the source code of this file.

Functions
def	Laelaps.Gpio.gpioReadValue (gpio)
	Read value of a GPIO pin. More...
def	Laelaps.Gpio.gpioWriteValue (gpio, value)
	Write a value to a GPIO pin. More...
def	Laelaps.Gpio.MotorCtlrChipSelectGpio (port, addrSel, addrLast)
	Laelaps specific chip select function using digital GPIO. More...
def	Laelaps.Gpio.MotorCtlrChipselectRts (port, addrSel, addrLast)
	Laelaps specific chip select function using RTS. More...
def	Laelaps.Gpio.enableMotorCtlrsPower (state)
	Enable/disable power to Laelaps motor controllers. More...
def	Laelaps.Gpio.areMotorCtlrsPowered ()
	Test if the motor controllers are powered. More...

Detailed Description

Laelaps Odroid GPIO control.

LastChangedDate

2016-02-02 13:47:13 -0700 (Tue, 02 Feb 2016)

Rev

4293

Author

: Robin Knight (robin.nosp@m..kni.nosp@m.ght@r.nosp@m.oadn.nosp@m.arrow.nosp@m.s.co.nosp@m.m)

Copyright

© 2015-2017. RoadNarrows LLC.
http://www.roadnarrows.com
All Rights Reserved

EULA@

Permission is hereby granted, without written agreement and without license or royalty fees, to use, copy, modify, and distribute this software and its documentation for any purpose, provided that (1) The above copyright notice and the following two paragraphs appear in all copies of the source code and (2) redistributions including binaries reproduces these notices in the supporting documentation. Substantial modifications to this software may be copyrighted by their authors and need not follow the licensing terms described here, provided that the new terms are clearly indicated in all files where they apply.

IN NO EVENT SHALL THE AUTHOR, ROADNARROWS LLC, OR ANY MEMBERS/EMPLOYEES OF ROADNARROW LLC OR DISTRIBUTORS OF THIS SOFTWARE BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE AUTHORS OR ANY OF THE ABOVE PARTIES HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

THE AUTHOR AND ROADNARROWS LLC SPECIFICALLY DISCLAIM ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

—@

Definition in file Gpio.py.

Function Documentation

def Laelaps.Gpio.areMotorCtlrsPowered

(

)

Test if the motor controllers are powered.

Returns

Returns True if powered, False if unpowered.

Definition at line 168 of file Gpio.py.

def areMotorCtlrsPowered():
  if gpioReadValue(GpioMotorCtlrEn) == '1':
    return True
  else:
    return False

def Laelaps.Gpio.enableMotorCtlrsPower

(

state

)

Enable/disable power to Laelaps motor controllers.

Parameters

state

True to enable, False to disable.

Definition at line 160 of file Gpio.py.

def enableMotorCtlrsPower(state):
  gpioWriteValue(GpioMotorCtlrEn, state);

#

def Laelaps.Gpio.gpioReadValue

(

gpio

)

Read value of a GPIO pin.

Parameters

gpio	Exported GPIO number.

Returns

On success returns '0' or '1'. On error, '' is returned.

Definition at line 68 of file Gpio.py.

def gpioReadValue(gpio):
  valFileName = "/sys/class/gpio/gpio%d/value" % (gpio)
  try:
    fp = open(valFileName, "r")
  except IOError as inst:
    print >>sys.stderr, "Error:", inst
    return ''
  try:
    val = fp.read(1)
  except IOError as inst:
    print >>sys.stderr, "Error:", inst
    val = ''
  fp.close()
  return val

#

def Laelaps.Gpio.gpioWriteValue	(		gpio,
			value
	)

Write a value to a GPIO pin.

Parameters

gpio	Exported GPIO number.
value	Value to write. If '0', 0, or False, value written is '0'. If '1', non-zero, or True, value written is '1'.

Returns

On success returns '0' or '1'. On error, '' is returned.

Definition at line 93 of file Gpio.py.

def gpioWriteValue(gpio, value):
  valFileName = "/sys/class/gpio/gpio%d/value" % (gpio)
  try:
    fp = open(valFileName, "w")
  except IOError as inst:
    print >>sys.stderr, "Error:", inst
    return ''
  if (value == '0') or (value == '1'):
    val = value
  elif value:
    val = '1'
  else:
    val = '0'
  try:
    val = fp.write(val+'\n')
  except IOError as inst:
    print >>sys.stderr, "Error:", inst
    val = ''
  fp.close()
  return val

#

def Laelaps.Gpio.MotorCtlrChipSelectGpio	(		port,
			addrSel,
			addrLast
	)

Laelaps specific chip select function using digital GPIO.

Note

Deprecated

The Laelaps uses GPIO 173 to select the front or rear motor controllers. For the Odroid, this pin is also the RTS line. Hardware flow control is not used, so this pin is available for signalling.

Parameters

port	Opened serial port (not used).
addrSel	Address of motor controller to be selected.
addrLast	Address of last motor controller selected.

Definition at line 127 of file Gpio.py.

def MotorCtlrChipSelectGpio(port, addrSel, addrLast):
  if addrSel != addrLast:
    if addrSel == MotorCtlrAddrFront:
      val = 1
    else:
      val = 0
    gpioWriteValue(GpioMotorCtlrCs, val);

#

def Laelaps.Gpio.MotorCtlrChipselectRts	(		port,
			addrSel,
			addrLast
	)

Laelaps specific chip select function using RTS.

Note

Deprecated

The RTS signal in current Odroid distro does not work, so this function is useless.

Parameters

port	Opened serial port.
addrSel	Address of motor controller to be selected.
addrLast	Address of last motor controller selected.

Definition at line 147 of file Gpio.py.

def MotorCtlrChipselectRts(port, addrSel, addrLast):
  if addrSel != addrLast:
    if addrSel == MotorCtlrAddrFront:
      level = True
    else:
      level = False
    port.setRTS(level)

#