ProgramXRFRelay.py

#  SET CYCLE PROGRAM
#
import serial
import datetime
print """
LLAP UTILITY TO SEND CISECO XRF MODULES INTO SLEEP CYCLE,- 
ONLY TESTED FOR THERMISTORS!
See:
http://openmicros.org/index.php/articles/87-llap-lightweight-local-automation-protocol/llap-devices-commands-and-instructions/122-xrf-firmware-temp
for details (above address should cut and paste).

NOTE! This program will simply hang if used to set an XRF module that is switched off.
Use 'ctrl+z' to exit if this happens.

This python file is written to set the XRF labelled "--" to cycle. This is the 
factory default.  If the selected device has been given a new ID (by sending 
"a--CHDEVIDXX", where "XX" is the new name and then sending "a--REBOOT---" 
to save it), the variable "devid" in this file will need to be edited.

The sleep interval is set by a 3 digit code (001 to 999), followed by D (days), 
H (hours), M (minutes) or S (guess what?). The default is 15 minutes = 015M

Once the settings commands are sent, this program sits and listens, displaying 
the time of each reading received. This allows you to verify that the new 
cycle is being followed by the XRF.

"""
#ID of devid to listen to 
devid = '--'
baud = 9600
port = '/dev/ttyAMA0'
interval = "001M"
# 4 readings an hour is enough to allow a couple to drop out and still get an hourly update
#
now = datetime.datetime.now()
print "Computer reports time as " + now.strftime("%H:%M %m-%d-%Y")
print "Set calibration  to " + interval
print "Use use ctrl+z to exit and then edit this file if you want to change this."
go = raw_input('Press return key to commit to this setting.')

print "Opening port "+ port + " at ", baud, " baud."
ser = serial.Serial(port, baud)
# Clear out anything in the read buffer
ser.flushInput()
# if this XRF has never been put into cycle before, this is all you need :

# See if it worked...
print "Monitoring cycle timing and waiting for battery reading at " + now.strftime("%H:%M %m-%d-%Y")
print "If interval is correct, use ctrl+z to exit"
while 1 :
# wait for message, if it's a battery reading we've go just 100 ms to send the WAKE call,
# so put all the checking the time and printing of details AFTER the reading/writing
# and make the if statement just one character long!
	if ser.inWaiting() > 0 :
		llapMsg = ser.read(ser.inWaiting())
		if "a--START" in llapMsg :
			ser.write('a'+devid+'CHDEVIDRA')
			ser.write('a'+devid+'REBOOT---')
			print ' '
			print '!!!!!!!!!!!!!!!!!!!!!!!!!'
			print '!Calibration signal sent!'
			print '!!!!!!!!!!!!!!!!!!!!!!!!!'
# Get time from system
		now = datetime.datetime.now()
		print 'Content = |' + llapMsg + "| detected at "+ now.strftime("%H:%M %m-%d-%Y")