This hazard is present only in pipelines that write in more than one pipe stage or allow an instruction to proceed even when a previous instruction is stalled. The DLX integer pipeline writes a register only in WB and avoids this class of hazards.
The first touchscreen phone was launched in 1992 by IBM.The IBM Simon is also referred as the first smartphone.Simon is the first smartphone to be incorporated with the features of a PDA.
Touch screen devices generally come with either resistive or capacitive screens. The type of screen dictates how the device reads user input. In turn, this affects the type of stylus needed to navigate the device, as the stylus must be compatible with the display type. Prior to the 2007 release of the iPhone, most touch screen devices featured resistive screens.