Volvo Repair: check engine light 850 turbo, flash flash flash, black boxes

Question
Just returned with a newly purchased '94 850 turbo wagon with 144,000 miles. Bought it about 400 miles from my home and on the drive back the check engine light came on. Car drove fine but I need to have it emissions inspected in my state. How do I pull the codes and how do I reset? Thanks for the help.

Answer
behind the passengers side head light are 2 small black boxes,1 marked A ,and 1 marked B.on box A there is a small wire insert the wire into the hole marked 2 then turn the ignition key to position 2 but not started.then on the box narked A push the small button for 1 second then release it.the small red light will flash a code back as a 3 digit number.there is a short pause between flashes for a single digit and long pause between the different numbers.example:
a 121 would look like this flash.....flash..flash....flash
write down each code,then after the first code repeats its self then press the button for 5 seconds the light will light when pressing button then go out when released,then the light will light steady again when it does press button fo 5 seconds again,this should have reset the check engine light.let me know the codes. i will tell what they refer to.
         Rege