raw a block diagram, define signals connecting the communicating blocks and describe the principle of operation of I$2$C interface. $[4$ marks$]$ b$)$ Assume that the serial port will return the following characters $5,2,$ and $6$ from the getchar$()$ function. What is the value of variable val in decimal after the following code completes its execution? Explain your answer. int i; int val$=0$; for $($i$=0$;i$<2$;i$++)\{$val$=$val$*8+$ getchar$()-\text{'}0\text{'}$; $\}[4$ marks$]$ c$)$ List two key properties of every type of memory.