Ticket #10828: acctest.py

#!/usr/bin/python
"""
 Test a lis3lv02d or similar accelerometer to see if it is
 installed and returning data

 Copyright (c) 2011 Saadia Baloch <saadia@laptop.org>
 Copyright (c) 2011 Martin Langhoff <martin@laptop.org>
 Copyright (c) 2011 One Laptop per Child Association

This program is free software; you can redistribute it and/or modify it
 under the terms of the GNU General Public License as published by the
 Free Software Foundation; either version 2, or (at your option) any
 later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

"""


ACCURACY  = 18
WIDTH     = 1200
HEIGHT    = 800
VARIATION = 7
""" The expectation is that values will vary,
    but be in a range of 7 points each way. 
"""
TREMBLE   = ACCURACY * 2 * VARIATION

import sys
import re
from optparse import OptionParser

posextract = re.compile("\(([-+]?\d+),([-+]?\d+),([-+]?\d+)\)")
def accelread(posfile):
    try:
        f = open(posfile, 'r')
        pos = f.read()
        f.close()
    except:
        print >> sys.stderr, "Cannot open or read position file %s . Perhaps the accelerometer driver is not installed" % posfile
        sys.exit(1)
        
    m = posextract.match(pos)
    if m:
        px = int(m.group(1))
        py = int(m.group(2))
        pz = int(m.group(3))
    else:
        print >> sys.stderr, "Accelerometer position file unreadable"
        sys.exit(1)
        
    return (px, py, pz)

def acceltest(rep, op):
    print >> sys.stderr, "Testing accelerometer %d times.  # means movement, _ means stationary\n" % rep
    
    for h in range(0,rep):
        minx = miny = minz = maxx = maxy = maxz = None

        for i in range(0, 100):
            (px, py, pz) = accelread(op.posfile)

            if (minx == None or px < minx):
                minx = px
            if (miny == None or py < miny):
                miny = py
            if (minz == None or pz < minz):
                minz = pz

            if (maxx == None or px > maxx):
                maxx = px
            if (maxy == None or py > maxy):
                maxy = py
            if (maxz == None or pz > maxz):
                maxz = pz

        px = maxx-minx
        py = maxy-miny
        pz = maxz-minz

        if px == 0 and py == 0 and pz == 0:
            print >> sys.stderr, "\nAccelerometer failed @ %d" % h
        #print "+"
        #print  >> sys.stderr, '='

        if px > TREMBLE or py > TREMBLE or pz > TREMBLE:
            sys.stderr.write('#')
        else:
            sys.stderr.write('_')
        sys.stderr.flush()

        # print sys.stderr, "X range is %d\nY range is %d\nZ range is %d" % ( px, py, pz)

    print >> sys.stderr, "\nAccelerometer test succeeded"



op = OptionParser(usage="%prog [options] repetitions")
op.add_option('--positionfile', dest='posfile',
              default='/sys/devices/platform/lis3lv02d/position',
              help='Override default position file')
(options, args) = op.parse_args()
rep = 100
if len(args) == 1:
    rep = int(args[0])

acceltest(rep, options)