Hello, I am fairly new to the AVR programming scene. I purchased an ATSTK200 programmer about a year and a bit ago and used it to program a few 8515's and everything worked well. I just tried programming some 2313's with it and it will let me read the device (doesn't give proper read) and whenever I try to program or erase it says AT90S2313 not detected. I thought I had a bad chip so I tried a couple different ones and get the same thing. I then tried an 8515 and get the same thing with that as well. This was on my laptop, I then tried it on a p233 running w98 and it worked fine. Two days later on the same P233 I am unable to program again same error messages I recieved on my laptop. I've tried two different power supplies (both AC and DC 12 volt) and tried three different computers, a dell laptop inspiron 3800 celaron 500, p233 with w98 and a k62-450 with w98 to no avail. Anyone have any ideas?