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.
Before the touch-tone phone, of course, rotary dials were the rule. There is no doubt that the touch-tone key pad was designed to mimic the rotary dial with the 1 on top and the 7-8-9 on the bottom. According to Bob Ford, of AT&T's Bell Laboratories, a second reason was that some phone-company research concluded that this configuration helped eliminate dialing errors.