Bi 5. Kim sot n cu thang1. Yu cu bi ton:Cho mt h thng n cu
thang, gm n led v 2 cng tc tt/bt K1, K2 nh trn hnh. Nguyn tc hot ng
nh sau: Khi K1 bm, c 8 n led cu thang s chuyn trng thi t bt -->
tt, hoc ngc ti, tt --> bt Khi K2 bm, tng t S dng thm 1 External
Timer m s xung nhp, t xc nh thi im K1, K2 c bm.Hy vit chng trnh hp
ng :a. Thc hin chc nng m t v K1, K2, Ledb. Trn giao din console, c
menu hin th tng s ln tt n, tng s ln bt n.c. Trn giao din console, c
menu hin th thi im bm K1, K2 gn nht, tnh theo s xung nhp m External
Timer ghi li (tickcount).
2. Thut tona. X l ngt S dng cc lnhli t2,0x22li t3,0x11li t4,0x44
bt s kin bm cng tc K1,K2 v External Timer Hm tang_xung: S dng thanh
ghi s6 lu thi im xung hin ti Hm bam_ct_k1: Bm cng tc K1 th t n sng
sang tt v ngc li Hm bam_ct_k2: Tng t hm bam_ct_k1 Hm on: Bt n Dng
lnh: li s1,0xffla t0, LEDSsb s1,0(t0)addi s2,s2,1(thanh ghi s2 lu s
ln bt n) Hm off:Tt n(Tng t hm off, dng thanh ghi s3 lu s ln tt n)b.
Vit menu In ra menu bng lnh:la a0,_menujal printf(menu l xu c khi
to) S dng lnh getchar,putchar yu cu ngi dng nhp s la chn ca menu c
gii hn yu cu lc nhp bng cch chuyn t dng k t v s nguyn sau so snh vi
cc la chn ca menujal getcharadd a0,v0,zeroaddi t7,v0,-48jal
putchar3. In ra Console v I/O:a. Menu:
b. La chn 1:Sau khi 4 ln bt n v 3 ln tt n
c. La chn 2:Thi im xung th 9 lu gi ln bm K1 gn nhtThi im xung th
7 lu gi ln bm K2 gn nht
4. Ton b code bi ton
#include #include #include #define PIO_SETUP2 0xffffea2a#define
SWITCHES 0xbf900000#define LEDS 0xbf900000#define BUTTONS
0xbfa00000 .dataslbat: .asciiz
"\n-----------------------------------------------\n\nSo lan bat
den: %d"enter: .asciiz "\n"sltat: .asciiz "\nSo lan tat den:
%d"tdbk1: .asciiz "\nThoi diem bam K1 gan nhat: %d"tdbk2: .asciiz
"\nThoi diem bam K2 gan nhat: %d"_menu: .asciiz
"\n\n\n-----------------------MENU-------------------------\n\n1.
Hien thi tong so lan dat tat den\n2. Hien thi thoi gian bat tat den
gan nhat\n3. Thoat\n\nLua chon: "_chon: .space 3thanks: .asciiz
"\n\nTHANKS YOU !!!"nhap_lai: .asciiz "\nNhap sai ! Nhap lai mot
gia tri tu ( 1 - 3): "
.text#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~#
GENERAL INTERRUPT SERVED ROUTINE for all
interrupts#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.globl
introutine.ent introutine.set reorder.set noat# Not warning if the
AT register is used
introutine:#--------------------------------------------------------#
SAVE the current REG FILE to
stack#-------------------------------------------------------- subu
sp, sp, 22*4 # Allocate space, 18 regs, 4 args sw AT, 4*4(sp) #
Save the registers on the stack sw v0, 5*4(sp) sw v1, 6*4(sp) sw
a0, 7*4(sp) sw a1, 8*4(sp) sw a2, 9*4(sp) sw a3, 10*4(sp) sw t0,
11*4(sp) sw t1, 12*4(sp) sw t2, 13*4(sp) sw t3, 14*4(sp) sw t4,
15*4(sp) sw t5, 16*4(sp) sw t6, 17*4(sp) sw t7, 18*4(sp) sw t8,
19*4(sp) sw t9, 20*4(sp) sw ra, 21*4(sp) # Note that 1*4(sp),
2*4(sp), and 3*4(sp) are # reserved for printf arguments .set
reorder #-------------------------------------------------------- #
Detect the CAUSE of Interrupt, maybe K1, K2, Timer and # the
instruction address in the main program when it happens (to return
later). #--------------------------------------------------------
mfc0 k0, C0_CAUSE # Retrieve the cause register -- (do ngat cung)
mfc0 k1, C0_EPC # Retrieve the
EPC#-------------------------------------------------------- # Get
the I/O port address # Used to detect K1, K2, timer were pressed
#-------------------------------------------------------- lui s0,
0xbfa0 # Place interrupt I/O port address in s0
#-------------------------------------------------------- # The
main function of GENERAL INTERRUPT SERVED ROUTINE # Print CAUSE,
EPC, I/O Port to console # K1: a3 = 22 # K2: a3 = 11 # EXT: a3 = 44
#-------------------------------------------------------- lbu a3,
0x0(s0)li t2,0x22li t3,0x11li t4,0x44beqa3,t4,tang_xungand
t5,a3,t2beq t5,t2,bam_ct_k1and t5,a3,t3beq t5,t3,bam_ct_k2j
donetang_xung:addi s6,s6,1 // tang xung len 1, s6 bien dem xung
(chu ky ngat dinh thoi external timer)j donebam_ct_k1:add
s4,s6,zero // s4 = thoi diem bam k1 gan nhatbeq s1,0xff,off // neu
trang thai den dang la 0xff tuc dang bat --> nhay den off de tat
denbeq s1,0x00,on//bam_ct_k2:add s5,s6,zero// s5 = thoi diem bam k2
gan nhatbeq s1,0xff,offbeq s1,0x00,onon:li s1,0xffla t0, LEDSsb
s1,0(t0)addi s2,s2,1 // s2 = so lan bat denj doneoff:li s1,0x00la
t0, LEDSsb s1,0(t0)addi s3,s3,1 // s3 = so lan tat den done:
#-------------------------------------------------------- # Reset
the I/O port address to zero after serving interrupt
#-------------------------------------------------------- sb
zero,0x0(s0) # Acknowledge interrupt, (resets latch)
#--------------------------------------------------------# RESTORE
the REG FILE from
STACK#-------------------------------------------------------- .set
noreorder lw ra, 21*4(sp) # Restore the registers from the stack lw
t9, 20*4(sp) lw t8, 18*4(sp) lw t7, 18*4(sp) lw t6, 17*4(sp) lw t5,
16*4(sp) lw t4, 15*4(sp) lw t3, 14*4(sp) lw t2, 13*4(sp) lw t1,
12*4(sp) lw t0, 11*4(sp) lw a3, 10*4(sp) lw a2, 9*4(sp) lw a1,
8*4(sp) lw a0, 7*4(sp) lw v1, 6*4(sp) lw v0, 5*4(sp) lw AT, 4*4(sp)
addu sp, sp, 22*4 # Return activation record
#-------------------------------------------------------- #
noreorder must be used here to force the # rfe-instruction to the
branch-delay slot jr k1 # Jump to EPC rfe # Return from exception #
Restores the status register .set reorder.end introutine
# The only purpose of the stub routine below is to call # the
real interrupt routine. It is used because it is # of fixed size
and easy to copy to the interrupt start # address location..ent
intstub.set noreorderintstub: j introutine nop.set reorder.end
intstub
.globl start # Start of the main program.ent startstart:la t0,
LEDS// load dia chi cua den vao t0lb s1, 0(t0) // lay trang thai
ban dau cua den va la bien luu trang thai cua denli s2, 0 // luu so
lan bat denli s3, 0 // luu so lan tat denli s4, 0 // thoi diem bam
k1 gan nhatli s5, 0 // thoi diem bam k2 gan nhatli s6, 0// dem xung
#---------------------------------------------------------- #
Enable IO PIN of K1, K2 buttons
#---------------------------------------------------------- lh a0,
PIO_SETUP2 # Enable button port interrupts andi a0, 0xbfff sh a0,
PIO_SETUP2
#---------------------------------------------------------- # Reset
I/O port address before enable interrupts
#---------------------------------------------------------- lui t0,
0xbfa0 # Place interrupt I/O port address in t0, t0 = 0xbfa0.0000
sb zero,0x0(t0) # Acknowledge interrupt, (resets latch)
#---------------------------------------------------------- #
Register the GENERAL INTERRUPT SERVED ROUTINE
#---------------------------------------------------------- la t0,
intstub # These instructions copy the stub la t1, 0x80000080 #
routine to address 0x80000080 lw t2, 0(t0) # Read the first
instruction in stub lw t3, 4(t0) # Read the second instruction sw
t2, 0(t1) # Store the first instruction sw t3, 4(t1) # Store the
second instruction
#---------------------------------------------------------- # Set
the status register to ENABLE EXPECTED INTERRUPTS # such as K1, K2,
timer and ENABLE THE GENERAL INTERRUPT
#---------------------------------------------------------- mfc0
v0, C0_SR # Retrieve the status register li v1, ~SR_BEV # Set the
BEV bit of the status and v0, v0, v1 # register to 0 (first
exception vector) ori v0, v0, 1 # Enable user defined interrupts
ori v0, v0,EXT_INT3 # Enable interrupt 3 (K1, K2, timer) mtc0 v0,
C0_SR # Update the status register
#---------------------------------------------------------- #
No-end loop, main program, to demo the effective of interrupt
#----------------------------------------------------------Loop:la
a0,_menu// in ra menujal printfLUA_CHON:loop1:jal getchar# Nhap su
lua chon menuadd a0,v0,zero#addi t7,v0,-48#jal putchar#la
a0,enter#jal
printf#lit4,1lit5,2lit6,3beqt4,t7,case1beqt5,t7,case2beqt6,t7,case3rechoice:la
a0,nhap_laijal printfjloop1Switch:case1://So lan tat/batla
a0,slbatadd a1,s2,zerojal printfla a0,sltatadd a1,s3,zerojal
printfj break_switch // break
case2:// Thoi diem su dung cac cong tac K1,K2la a0,tdbk1add
a1,s4,zerojal printflaa0,tdbk2add a1,s5,zerojal printfj
break_switchcase3://--------------------------------------------------//
in ra xau cam on va thoat chuong
trinh//--------------------------------------------------la
a0,thanksjal printfj THOATbreak_switch:j Loop
THOAT:j THOAT.end start
