How to set up one wire bus on GPIO pin


http://squidge.sourceforge.net/w1/
but this link did not get you to the final value as one package was not installed

This works!
http://openrouter.info/forum/viewtopic.php?f=30&t=396


opkg update
opkg install kmod-w1 
opkg install kmod-w1-gpio-custom 
opkg install kmod-w1-slave-therm
opkg install bc 


nano /etc/modules.d/55-w1-gpio-custom
w1-gpio-custom bus0=0,13,0
this is line RX of the serial port nr GPIO13

connect sensor out to this line
connect 5V and gNd to sensor.Need pullup resistor from +5V. 5V can get from one of regulators onboard. CPU is 3.3V. 5V data level from sensor did not kill it.


Now sensors appear in the directory
/sys/devices/w1 bus master


28-000002def034            uevent                     w1_master_name             w1_master_search
28-000002defad3            w1_master_add              w1_master_pointer          w1_master_slave_count
driver                     w1_master_attempts         w1_master_pullup           w1_master_slaves
subsystem                  w1_master_max_slave_count  w1_master_remove           w1_master_timeout


cd 28-000002def034
 cat w1_slave
80 01 4b 46 7f ff 10 10 c6 : crc=c6 YES
80 01 4b 46 7f ff 10 10 c6 t=24000

cat /sys/devices/w1\ bus\ master/28-000002def034/w1_slave


#============================================================================================================
# Code checking for bad values
# if e=o after checks then can update temperature database

for i in {1..10};do

t1=$(cat  /sys/devices/w1\ bus\ master/28-000002def034/w1_slave | tail -1 | awk -F "=" '{ print $2; }')
t2=$(cat  /sys/devices/w1\ bus\ master/28-000002defad3/w1_slave | tail -1 | awk -F "=" '{ print $2; }')

e=0; echo $t1 "  " $t2
if [ "$t1" = "-62" ];then echo "bad value"; e=1 ; else echo "fine"; fi
if [ "$t2" = "-62" ];then echo "bad value"; e=1 ; else echo "fine"; fi
if [ "$t1" = "85000" ];then echo "bad value"; e=1 ; else echo "fine"; fi
if [ "$t2" = "85000" ];then echo "bad value"; e=1 ; else echo "fine"; fi
if [ -z "$t1" ];then echo "bad value"; e=1 ; else echo "fine"; fi
if [ -z "$t2" ];then echo "bad value"; e=1 ; else echo "fine"; fi

echo "error = "$e
if [ "$e" -eq  "0" ];then
echo "update database "
t1=$(echo "scale=3;$t1/1000" | bc -l)
t2=$(echo "scale=3;$t2/1000" | bc -l)
echo $t1 "  " $t2
break
else echo "bad values"
$t1=-1
$t2=-1
fi
done
#============================================================================================================