;here, we assign our POINTER to a ›;special memory location.  This is›;how we can use POINTERs like a POKE›;statement.› ›;In BASIC try this:›; 10 POKE 710,0›;and the same thing will happen.›;The number 0 is the way the computer›;knows black.  And 710 is the    ›;address where your Atari keeps the›;text background color.›››PROC background()››  BYTE POINTER bkgnd››  bkgnd=710›  bkgnd^=0››RETURN›››;Here I will show you how a POINTER›;can change a parameter.  Let's say›;an employee wants to deduct $20›;from his salary for the United Way›;every paycheck.›;Now you can just send his salary›;to this PROC and it will make this›;decuction for you.  ››;I assume most of you think it›;would be easier to use a global›;salary variable.››;Yes, that is another way to do it ›;but this PROC would loose its›;"independence."››PROC chng_value(CARD POINTER wage)››  PrintE("United Way deduction: $20")›  wage^=wage^-20›RETURN››PROC main()››  CARD salary›››  background()››  salary=300›  Print("Your salary is: ")›  PrintCE(salary)››                       ;Send the›  chng_value(@salary)  ;deduction PROC›                       ;the address of›                       ;the variable›››  Print("Your takehome pay is: ")›  PrintCE(salary)›  ›RETURN›››