Casting of value assigned to pointer rvalue

Projects Programming
1

Hi,
I am a c beginner and I am trying to understand an expression I came across in some example code in the text book I'm using:

byte *b;
b = (byte *) &myPeople[ index];
If it wasn't for the asterisk I would interpret this as meaning the lvalue of mPeople[index] is converted to a byte data type and assigned to the pointer (b) rvalue. However what does the asterisk signify? Is it simply to indicate a pointer is involved?
Would appreciate clarification

2 
byte *b;

Declares a pointer to a byte (not storage for a byte)

Then. For Example if myPeople is array of int

myPeople[ index];

would give you the int value of myPeople at array position index

but using the & sign tells the compilor you want the address of that value not the value

hence

b = (byte *) &myPeople[ index];

b now points to the value in myPeople[index]

3

As I understand it, the expression (byte *) means that whatever follows is the address of a byte, so that address is stored in the pointer b (previously declared to be a pointer to a byte). b will then point to the first byte of myPeople[index], an array element that may be of some other type.

4

(byte *)

This means cast this to a pointer to byte

if myPeople was an array of bytes you shouldnt need to cast it, because the compilor should know that &myPeople[index] would be a pointer to byte.

i.e this compiles

void setup() {
  // put your setup code here, to run once:
byte myPeople[10];
byte *b;

b=&myPeople[2];
}

void loop() {
  // put your main code here, to run repeatedly: 
  
}
5

Thanks for the help, I now understand what (byte *) means