' this will monitor and report the 12V Battery and Current being used out to a serial port
'  at 4800 bd.  This is to be used with the SWASC Power Monitor - Computer circiut.
' This uses a PICAXE-18x so the current and voltage can be displayed onto a 2 x 16 line LCD
'
'  Paul Hamilton - 20070916
'


' Local Variables
SYMBOL LOOPDELAY=500

' clear the LCD screen
 serout 7,N2400, (254,1)
 pause 30
 
MAIN:
 ' Blink a debug LED - one reading per blink/loop
 high 1  ' set the LED on port 1 ON
 pause LOOPDELAY
 low 1   ' set LED off
 pause LOOPDELAY
 ' lets read what the voltage is on the resistance ladder junction
 READADC 1,b1
 w2=b1*10/16	' convert the reading from units to voltage * 10, ie. 119 = 11.9 Volts
 ' lets read what the current is being reported by the ACS712
 READADC 0,b2
 b3=b2-121
 ' because I am using a ACS712, Need to watch out for readings below 0 (ie 255)
 ' I really should be using a ACS713, then I wouldn't have this problem. 
 if b3<253 then SKIP
   b3=0
 SKIP:
 sertxd ("V: ", #b1,",  A: ", #b3,13,10)   ' send data to PC
 serout 7, N2400, (254,128,"V: ",#w2,"  ")	' display the Voltage.  Need to mentally devide by 10
 serout 7, N2400, (254,192,"A: ",#b3,"  ")	' display the current.  Need to mentally devide by 10.
 if b1>197 then MAIN
 sound 6,(110,20,80,30)  ' plays a Voltage Low warning sound
goto MAIN