first do you have the correct computer in your mazada if this is a used car that u have purchased then check that first . I had a a code on a mazada and found out that it had the wrong computer in it. Now if that is not the problem then the code you are getting is saying that you are not getting the correct voltage either to or from the computer to the fisr O2sensor. This is the one beofre or in front of the cat convertor. you can also type in Bosch or even O2 sensor and do a search on the net and maybe get a little more info

 You can alsoo type in Mazada forums and find info

 Most likely your o2 sensor is bad or a wire is broke you should be able to read the voltage with the didgi software  and then do a test with a volt meter to see if it is senor or wiring

 hope this helps