Background: This document outlines the results of a reverse engineering effort of the protocol which exists between AVRStudio and the AVR JTAG-Ice.
Something to note is that the protocol supports dynamic bitrate changes. AVRStudio does indeed change the bitrate "mid-stream". Specifically, it seems to speed it up to 115200bps just prior to downloading (and possibly uploading) blocks of date to the JTAG-Ice. After the download, the bitrate is restored to 19200bps. 。。。。。。。。