RosettaCodeData/Task/Address-of-a-variable/RISC-V-Assembly/address-of-a-variable.asm
2025-08-11 18:05:26 -07:00

128 lines
4.3 KiB
NASM

# riscv assembly raspberry pico2 rp2350
# program adrvariable.s
# connexion putty com3
/*********************************************/
/* CONSTANTES */
/********************************************/
/* for this file see risc-v task include a file */
.include "../../constantesRiscv.inc"
/*******************************************/
/* INITIALED DATAS */
/*******************************************/
.data
szMessStart: .asciz "Program riscv start.\r\n"
szCariageReturn: .asciz "\r\n"
.align 2
tabValues: .int 1,2,3,4
/*******************************************/
/* UNINITIALED DATA */
/*******************************************/
.bss
.align 2
sConvArea: .skip 24
ivalue1: .skip 4
/**********************************************/
/* SECTION CODE */
/**********************************************/
.text
.global main
main:
call stdio_init_all # général init
1: # start loop connexion
li a0,0 # raz argument register
call tud_cdc_n_connected # waiting for USB connection
beqz a0,1b # return code = zero ?
la a0,szMessStart # message address
call writeString # display message
la t1,ivalue1 # variable address
lw a0,(t1) # load word value
call displayResult
la t1,ivalue1 # variable address
li t0,12345 # new value
sw t0,(t1) # store word value
la t1,ivalue1 # variable address
lw a0,(t1) # load value for control
call displayResult
la t1,tabValues # load array address
lw a0,8(t1) # load value at byte 8 of array
call displayResult
la t1,tabValues # load array address
li t2,3 # init index value
slli t2,t2,2 # multiply index by 5 (integer size)
add t2,t2,t1 # add offset to array address
lw a0,(t2) # load value of index
call displayResult
call getchar
100: # final loop
j 100b
/**********************************************/
/* displayResult */
/**********************************************/
/* a0 value */
.equ LGZONECONV, 20
displayResult:
addi sp, sp, -4 # reserve stack
sw ra, 0(sp)
la a1,sConvArea # conversion result address
call conversion10 # conversion decimal
la a0,sConvArea # message address
call writeString # display message
la a0,szCariageReturn
call writeString
100:
lw ra, 0(sp)
addi sp, sp, 4
ret
/**********************************************/
/* decimal conversion */
/**********************************************/
/* a0 value */
/* a1 conversion array address */
.equ LGZONECONV, 20
conversion10:
addi sp, sp, -4
sw ra, 0(sp)
li t1,LGZONECONV
li t2,10 # divisor
1:
rem t4,a0,t2 # division remainder by 10
addi t4,t4,48 # convert to decimal
add t5,a1,t1 # store character position
sb t4,(t5) # store byte
div a0,a0,t2 # compute quotient
beq a0,x0,2f # compare to 0
addi t1,t1,-1 # decrement store position
bgt t1,x0,1b # and loop if position is ok
2:
li t2,0 # raz indice
li t3,LGZONECONV
3: # loop to transfer result at begining conversion area
add t5,a1,t1 # compute start position
lb t4,(t5) # load byte
add t5,a1,t2 # compute new position
sb t4,(t5) # and store byte
addi t2,t2,1 # increment indice
addi t1,t1,1
ble t1,t3,3b # and loop if indice <= area size
add t5,a1,t2 # increment final position
sb x0,(t5) # and store byte final zero
mv a0,t2 # return size conversion
100:
lw ra, 0(sp)
addi sp, sp, 4
ret
/************************************/
/* file include Fonctions */
/***********************************/
/* for this file see risc-v task include a file */
.include "../../includeFunctions.s"