Help with Maxim Ibutton "IF THEN ELSE" statements please

[andybarrett1]

Code

mainloop: Owout ibutton,1,[$33]
pause 100
owin ibutton,0,[Serial[0],Serial[1],Serial[2],Serial[3],Serial[4],Serial[5],Serial[6],Serial[7]]

If Serial[1]=$15 and Serial[2]=$D3 and Serial[3]=$7D AND Serial[4]=$16 AND Serial[5]=$00 AND Serial[6]=$00 then correct1
If Serial[1]=$68 and Serial[2]=$36 and Serial[3]=$4F AND Serial[4]=$17 AND Serial[5]=$00 AND Serial[6]=$00 then correct2
If Serial[1]=$1E and Serial[2]=$1A and Serial[3]=$2C AND Serial[4]=$17 AND Serial[5]=$00 AND Serial[6]=$00 then correct3
If Serial[1]=$F0 and Serial[2]=$66 and Serial[3]=$2C AND Serial[4]=$17 AND Serial[5]=$00 AND Serial[6]=$00 then nocache
gosub wrong
Goto mainloop

Hi all...

Tried the above and variants of it....It is now just going staight to the gosub routine (wrong) I suspect because with no Ibutton in place the "Serial Number" is after all wrong!!

Help........!!!!