Compiler directive to handle each dimensioned variable as XRAM variable.
$DEFAULT XRAM | IRAM
When you are using many XRAM variables it make sense to set this option, so you don't have to type XRAM each time.
To dimension a variable to be stored into IRAM, specify IRAM in that case.
Dim X As Integer 'will go to XRAM
Dim Z As Iram Integer 'will be stored in IRAM