Random number generator in AVR Studio (no C or any other programming language!)

so I have this question, I have been given a task to do a bombard game with AVR Studio. To be true, I have no clue on how to use AVR and my programming is not so good as well. I got my ships done somehow, but now I need a random number generator. Have been looking throughout Internet for about 2 days now, only found source codes in C, in Java, in absolutely every other language but not the one I need. Could anyone suggest me in what to write for the RAND? for now, my source code looks like this:

;ports

.equ PORTC = $15    ;port C address

.equ DDRC  = $14

.equ PORTA = $15    ;port A address

.equ DDRA  = $14

;registers

.def leds = r16     ;storing data for leds

.def temp = r18     ;Temporary storage register

.def save = r19     ;Temporary storage register for status registers

.def YL   = r20     ;Defining low bite of Y

.def YH   = r21     ;Defining high bite of Y

;

.equ SREG = $3F     ;Status Register Address

.equ SPH  = $3E     ;High bite Stack Pointer address

.equ SPL  = $3D     ;Low bite Stack Pointer address

.equ RAMEND = $25F  ;Stack Address

;Random number generator

        ldi r16, $80

        ldi r17, $C0


;Set stack pointer to registers

        ldi temp,high(RAMEND)

        out SPH,temp

        ldi temp,low(RAMEND)

        out SPL,temp

;Initialise output ports

        ldi temp, $ff

        out DDRC, temp

clear:  clc

;       clr leds

        out PORTC, leds

        rjmp SHIP2_prep

SHIP1_prep: ldi leds, $80

        rjmp SHIPS



SHIP2_prep: ldi leds, $80

        out PORTC, leds

        ldi leds, $C0

        rjmp SHIPS



SHIP3_prep: ldi leds, $80

        out PORTC, leds

        ldi leds, $C0

        out PORTC, leds

        ldi leds, $E0

        rjmp SHIPS

;Rotate ships right

SHIPS:  out PORTC, leds

;       rcall delay

        ror leds

        brcs clear

        rjmp SHIPS


;delay: in  save,SREG

;       ldi YH,high($FF9C)

;       ldi YL,low($FF9C)

loop:   sbiw Y,1

        brne loop

        out SREG, save

        ret