Keyboard input/Keypress check: Difference between revisions

=={{header|ARM Assembly}}==

{{works with|as|Raspberry Pi}}

<lang ARM Assembly>

/* Programme assembleur ARM Raspberry */

/* Assembleur ARM Raspberry : Vincent Leboulou */

/* Blog : http://assembleurarmpi.blogspot.fr/ */

/* modèle B 512MO */

/************************************/

/* Constantes */

/************************************/

.equ STDIN, 0 @ Linux input console

.equ STDOUT, 1 @ Linux output console

.equ EXIT, 1 @ Linux syscall

.equ READ, 3 @ Linux syscall

.equ WRITE, 4 @ Linux syscall

.equ IOCTL, 0x36 @ Linux syscall

.equ SIGACTION, 0x43 @ Linux syscall

.equ SYSPOLL, 0xA8 @ Linux syscall

.equ TCGETS, 0x5401

.equ TCSETS, 0x5402

.equ ICANON, 2

.equ ECHO, 10

.equ POLLIN, 1

.equ SIGINT, 2 @ Issued if the user sends an interrupt signal (Ctrl + C)

.equ SIGQUIT, 3 @ Issued if the user sends a quit signal (Ctrl + D)

.equ SIGTERM, 15 @ Software termination signal (sent by kill by default)

.equ SIGTTOU, 22 @

.equ TAILLEBUFFER, 10

/*******************************************/

/* Structures */

/********************************************/

/* structure termios see doc linux*/

.struct 0

term_c_iflag: @ input modes

.struct term_c_iflag + 4

term_c_oflag: @ output modes

.struct term_c_oflag + 4

term_c_cflag: @ control modes

.struct term_c_cflag + 4

term_c_lflag: @ local modes

.struct term_c_lflag + 4

term_c_cc: @ special characters

.struct term_c_cc + 20 @ see length if necessary

term_fin:

/* structure sigaction see doc linux */

.struct 0

sa_handler:

.struct sa_handler + 4

sa_mask:

.struct sa_mask + 4

sa_flags:

.struct sa_flags + 4

sa_sigaction:

.struct sa_sigaction + 4

sa_fin:

/* structure poll see doc linux */

.struct 0

poll_fd: @ File Descriptor

.struct poll_fd + 4

poll_events: @ events mask

.struct poll_events + 4

poll_revents: @ events returned

.struct poll_revents + 4

poll_fin:

/*********************************/

/* Initialized data */

/*********************************/

.data

szMessPgmOk: .asciz "End program OK.\n"

szMessErreur: .asciz "Error detected.\n"

sMessResult: .ascii "Value : "

sMessValeur: .fill 11, 1, ' ' @ size => 11

szCarriageReturn: .asciz "\n"

/*************************************************/

szMessErr: .ascii "Error code hexa : "

sHexa: .space 9,' '

.ascii " decimal : "

sDeci: .space 15,' '

.asciz "\n"

szMessKey: .ascii "Value key ==>"

sHexaKey: .space 9,' '

.asciz "\n"

.align 4

/*********************************/

/* UnInitialized data */

/*********************************/

.bss

.align 4

iEnd: .skip 4 @ 0 loop 1 = end loop

iTouche: .skip 4 @ value key pressed

stOldtio: .skip term_fin @ old terminal state

stCurtio: .skip term_fin @ current terminal state

stSigAction: .skip sa_fin @ area signal structure

stSigAction1: .skip sa_fin

stPoll1: .skip poll_fin @ area poll structure

stPoll2: .skip poll_fin

/*********************************/

/* code section */

/*********************************/

.text

.global main

main: @ entry of program

/* read terminal state */

mov r0,#STDIN @ input console

mov r1,#TCGETS

ldr r2,iAdrstOldtio

mov r7, #IOCTL @ call system Linux

svc #0

cmp r0,#0 @ error ?

beq 1f

ldr r1,iAdrszMessErreur @ error message

bl displayError

b 100f

1:

adr r0,sighandler @ adresse routine traitement signal

ldr r1,iAdrstSigAction @ adresse structure sigaction

str r0,[r1,#sa_handler] @ maj handler

mov r0,#SIGINT @ signal type

ldr r1,iAdrstSigAction

mov r2,#0 @ NULL

mov r7, #SIGACTION @ call system

svc #0

cmp r0,#0 @ error ?

bne 98f

mov r0,#SIGQUIT

ldr r1,iAdrstSigAction

mov r2,#0 @ NULL

mov r7, #SIGACTION @ call system

svc #0

cmp r0,#0 @ error ?

bne 98f

mov r0,#SIGTERM

ldr r1,iAdrstSigAction

mov r2,#0 @ NULL

mov r7, #SIGACTION @ appel systeme

svc #0

cmp r0,#0

bne 98f

@

adr r0,iAdrSIG_IGN @ address signal igonre function

ldr r1,iAdrstSigAction1

str r0,[r1,#sa_handler]

mov r0,#SIGTTOU @invalidate other process signal

ldr r1,iAdrstSigAction1

mov r2,#0 @ NULL

mov r7,#SIGACTION @ call system

svc #0

cmp r0,#0

bne 98f

@

/* read terminal current state */

mov r0,#STDIN

mov r1,#TCGETS

ldr r2,iAdrstCurtio @ address current termio

mov r7,#IOCTL @ call systeme

svc #0

cmp r0,#0 @ error ?

bne 98f

mov r2,#ICANON | ECHO @ no key pressed echo on display

mvn r2,r2 @ and one key

ldr r1,iAdrstCurtio

ldr r3,[r1,#term_c_lflag]

and r3,r2 @ add flags

str r3,[r1,#term_c_lflag] @ and store

mov r0,#STDIN @ maj terminal current state

mov r1,#TCSETS

ldr r2,iAdrstCurtio

mov r7, #IOCTL @ call system

svc #0

cmp r0,#0

bne 98f

@

2: @ loop waiting key

ldr r0,iAdriEnd @ if signal ctrl-c -> end

ldr r0,[r0]

cmp r0,#0

bne 3f

ldr r0,iAdrstPoll1 @ address structure poll

mov r1,#STDIN

str r1,[r0,#poll_fd] @ maj FD

mov r1,#POLLIN @ action code

str r1,[r0,#poll_events]

mov r1,#1 @ items number structure poll

mov r2,#0 @ timeout = 0

mov r7,#SYSPOLL @ call system POLL

svc #0

cmp r0,#0 @ key pressed ?

ble 2b @ no key pressed -> loop

@ read key

mov r0,#STDIN @ File Descriptor

ldr r1,iAdriTouche @ buffer address

mov r2,#TAILLEBUFFER @ buffer size

mov r7,#READ @ read key

svc #0

cmp r0,#0 @ error ?

ble 98f

ldr r2,iAdriTouche @ key address

ldr r0,[r2]

ldr r1,iAdrsHexaKey

bl conversion16 @ conversion hexa

ldr r0,iAdrszMessKey @ display key value in hexa

bl affichageMess

ldrb r0,[r2] @ key value

cmp r0,#113 @ saisie q ?

beq 3f

cmp r0,#81 @ saisie Q ?

beq 3f

mov r0,#0

str r0,[r2] @ raz key area

b 2b @ loop

3: @ end loop display Ok message

ldr r0,iAdrszMessPgmOk

bl affichageMess

b 99f

98: @ error display

ldr r1,iAdrszMessErreur @ error message

bl displayError

99: @ end then restaur begin state terminal

mov r0,#STDIN

mov r1,#TCSETS

ldr r2,iAdrstOldtio

mov r7,#IOCTL @ call system

svc #0

cmp r0,#0

beq 100f

ldr r1,iAdrszMessErreur @ error message

bl displayError

100: @ standard end of the program

mov r0, #0 @ return code

mov r7, #EXIT @ request to exit program

svc #0 @ perform the system call

iAdrsMessValeur: .int sMessValeur

iAdrszMessErreur: .int szMessErreur

iAdrszCarriageReturn: .int szCarriageReturn

iAdrstOldtio: .int stOldtio

iAdrstCurtio: .int stCurtio

iAdrstSigAction: .int stSigAction

iAdrstSigAction1: .int stSigAction1

iAdrszMessPgmOk: .int szMessPgmOk

iAdrsMessResult: .int sMessResult

iAdrSIG_IGN: .int 1

iAdriEnd: .int iEnd

iAdrstPoll1: .int stPoll1

iAdriTouche: .int iTouche

iAdrszMessKey: .int szMessKey

iAdrsHexaKey: .int sHexaKey

/******************************************************************/

/* traitement du signal */

/******************************************************************/

/* r0 contains */

sighandler:

push {r0,r1}

ldr r0,iAdriEnd

mov r1,#1 @ maj zone end

str r1,[r0]

pop {r0,r1}

bx lr

/***************************************************/

/* display error message */

/***************************************************/

/* r0 contains error code r1 : message address */

displayError:

push {r0-r2,lr} @ save registers

mov r2,r0 @ save error code

mov r0,r1

bl affichageMess

mov r0,r2 @ error code

ldr r1,iAdrsHexa

bl conversion16 @ conversion hexa

mov r0,r2 @ error code

ldr r1,iAdrsDeci @ result address

bl conversion10 @ conversion decimale

ldr r0,iAdrszMessErr @ display error message

bl affichageMess

100:

pop {r0-r2,lr} @ restaur registers

bx lr @ return

iAdrszMessErr: .int szMessErr

iAdrsHexa: .int sHexa

iAdrsDeci: .int sDeci

/******************************************************************/

/* display text with size calculation */

/******************************************************************/

/* r0 contains the address of the message */

affichageMess:

push {r0,r1,r2,r7,lr} @ save registres

mov r2,#0 @ counter length

1: @ loop length calculation

ldrb r1,[r0,r2] @ read octet start position + index

cmp r1,#0 @ if 0 its over

addne r2,r2,#1 @ else add 1 in the length

bne 1b @ and loop

@ so here r2 contains the length of the message

mov r1,r0 @ address message in r1

mov r0,#STDOUT @ code to write to the standard output Linux

mov r7, #WRITE @ code call system "write"

svc #0 @ call systeme

pop {r0,r1,r2,r7,lr} @ restaur registers

bx lr @ return

/******************************************************************/

/* Converting a register to a decimal unsigned */

/******************************************************************/

/* r0 contains value and r1 address area */

/* r0 return size of result (no zero final in area) */

/* area size => 11 bytes */

.equ LGZONECAL, 10

conversion10:

push {r1-r4,lr} @ save registers

mov r3,r1

mov r2,#LGZONECAL

1: @ start loop

bl divisionpar10U @ unsigned r0 <- dividende. quotient ->r0 reste -> r1

add r1,#48 @ digit

strb r1,[r3,r2] @ store digit on area

cmp r0,#0 @ stop if quotient = 0

subne r2,#1 @ else previous position

bne 1b @ and loop

@ and move digit from left of area

mov r4,#0

2:

ldrb r1,[r3,r2]

strb r1,[r3,r4]

add r2,#1

add r4,#1

cmp r2,#LGZONECAL

ble 2b

@ and move spaces in end on area

mov r0,r4 @ result length

mov r1,#' ' @ space

3:

strb r1,[r3,r4] @ store space in area

add r4,#1 @ next position

cmp r4,#LGZONECAL

ble 3b @ loop if r4 <= area size

100:

pop {r1-r4,lr} @ restaur registres

bx lr @return

/***************************************************/

/* division par 10 unsigned */

/***************************************************/

/* r0 dividende */

/* r0 quotient */

/* r1 remainder */

divisionpar10U:

push {r2,r3,r4, lr}

mov r4,r0 @ save value

//mov r3,#0xCCCD @ r3 <- magic_number lower raspberry 3

//movt r3,#0xCCCC @ r3 <- magic_number higter raspberry 3

ldr r3,iMagicNumber @ r3 <- magic_number raspberry 1 2

umull r1, r2, r3, r0 @ r1<- Lower32Bits(r1*r0) r2<- Upper32Bits(r1*r0)

mov r0, r2, LSR #3 @ r2 <- r2 >> shift 3

add r2,r0,r0, lsl #2 @ r2 <- r0 * 5

sub r1,r4,r2, lsl #1 @ r1 <- r4 - (r2 * 2) = r4 - (r0 * 10)

pop {r2,r3,r4,lr}

bx lr @ leave function

iMagicNumber: .int 0xCCCCCCCD

/******************************************************************/

/* Converting a register to hexadecimal */

/******************************************************************/

/* r0 contains value and r1 address area */

conversion16:

push {r1-r4,lr} @ save registers

mov r2,#28 @ start bit position

mov r4,#0xF0000000 @ mask

mov r3,r0 @ save entry value

1: @ start loop

and r0,r3,r4 @value register and mask

lsr r0,r2 @ move right

cmp r0,#10 @ compare value

addlt r0,#48 @ <10 ->digit

addge r0,#55 @ >10 ->letter A-F

strb r0,[r1],#1 @ store digit on area and + 1 in area address

lsr r4,#4 @ shift mask 4 positions

subs r2,#4 @ counter bits - 4 <= zero ?

bge 1b @ no -> loop

100:

pop {r1-r4,lr} @ restaur registers

bx lr @return

</lang>