label .equ value [, page]
This assigns a label with a particular value, so you can then use the label in expressions rather than the constant each time. For example:
do_something = $5421, 3 size_of_array .equ 30 and_factor = %00001111 ; ... ; Select page: ld a,:do_something out (page_sel_port),a ; Do something ld b, size_of_array _loop: ld a, (hl) call do_something and and_factor ld (hl), a inc hl djnz _loop
There is a slight difference between the using = and .equ. = allows you to redefine a label; .equ doesn't.
_label _label = 0 ; Works _label .equ 0 ; Displays an error