For EVO 7/8/9 We use the Tactrix OpenPort 1.3 USB datalogging cable from www.TunerTools.com to make the connection from the laptop to the ECU for logging variables such as RPM, Timing, Knock, Narrowband 02, LoadCalc, TPS etc...If you're a member or www.racevideoforums.com and enter promo code RACEVIDEO you will receive 5% off http://tunertools.com/proddetail.asp?prod=TAC-OpenPort1.3U For EVO 10's you'll need the Tactrix OpenPort 2.0 cable, this also works on the 7/8/9 but is a little more expensive http://www.tactrix.com/product_info.php?products_id=40
We recommend purchasing a wb02 kit through www.TunerTools.com as well. If you're a member of www.racevideoforums.com enter promo code RACEVIDEO you'll get 5% off. This is the kit we use on the Mellon Tuning EVO http://tunertools.com/proddetail.asp?prod=IN-3796 You'll also need to pick up a serial to usb adapter cable from your local computer store and it will work well with Evoscan for logging. The dynex brand from Bestbuy in particular has been successful
We use ECUFlash from www.openecu.org to download the stock ROM out of the ECU and to flash our custom ROM. It's free and works on EVOs and Subarus for adjusting the fuel and timing maps etc...
Here's a video of Mellon demonstrating how to connect the Tactrix ODBII USB logging cable, download the stock rom with Ecuflash, log with Evoscan and upload your new Mellon Tuning flash file.