Oakland CPM Archive/oakcpm.iso/sigm/vol167/vti.asm

Assembly Source File | 1984-04-29 | 7.9 KB | 715 lines

;    org 0100H
    org 9000H

    jmp main

go:    equ    ge
chin:    equ    0C20H    ;POLY-88 WH0 (keyboard wormhole)
;chin:    equ    read    ;subroutine to read VDM (port EC)

vorg:    equ    0F800H
vsiz:    equ    00400H
rsiz    equ    00040H
msk:    equ    00CC9H
wye:    equ    00CCAH
eks:    equ    00CCBH
wy:    equ    00CCCH
ex:    equ    00CCDH

;    move cursor up one pixel

ypl:    lxi h,msk
    mov a,m
    ani 024H
    jnz yp1
    mov a,m
    rlc
    mov m,a
    ret
yp1:    rrc
    rrc
    mov m,a
    lda wye
    sui 010H
    sta wye
    ret

;    move cursor down one pixel

ymi:    lxi h,msk
    mov a,m
    ani 009H
    jnz ym1
    mov a,m
    rrc
    mov m,a
    ret
ym1:    rlc
    rlc
    mov m,a
    lda wye
    adi 010H
    sta wye
    ret

;    move cursor right one pixel

xpl:    lxi h,msk
    mov a,m
    ani 007H
    jnz xp1
    mov a,m
    rrc
    rrc
    rrc
    mov m,a
    ret
xp1:    rlc
    rlc
    rlc
    mov m,a
    lda eks
    adi 004H
    sta eks
    ret

;    move cursor left one pixel

xmi:    lxi h,msk
    mov a,m
    ani 038H
    jnz xm1
    mov a,m
    rlc
    rlc
    rlc
    mov m,a
    ret
xm1:    rrc
    rrc
    rrc
    mov m,a
    lda eks
    sui 004H
    sta eks
    ret

;    load A with the bit mask, HL with a byte address
;    given the cursor positioning data at (msk,wye,eks)

dot:    lhld wye
    mov a,h
    mvi h,03EH
    dad h
    dad h
    rrc
    rrc
    ora l
    mov l,a
    lda msk
    ret

;    home the cursor

home:    lxi h,8080H
    shld wye
    mvi a,008H
    sta msk
    ret

;    extinguish the cursor

cuex:    call dot
    ora m
    mov m,a
    ret

;    light the cursor

culi:    call dot
    cma
    ana m
    mov m,a
    ret

;    reverse the cursor

crev:    call dot
    xra m
    mov m,a
    ret

;    sense the cursor

cuse:    call dot
    ana m
    ani 03FH
    ret

;    clear the whole screen to black

blak:    lxi d,vsiz
    lxi h,vorg
bl1:    mvi m,0FFH
    inx h
    dcr e
    jnz bl1
    dcr d
    jnz bl1
    ret

;    clear the whole screen to white

whit:    lxi d,vsiz
    lxi h,vorg
wh1:    mvi m,080H
    inx h
    dcr e
    jnz wh1
    dcr d
    jnz wh1
    ret

;    reverse the whole screen

reve:    lxi d,vsiz
    lxi h,vorg
rev1:    mov a,m
    xri 03FH
    mov m,a
    inx h
    dcr e
    jnz rev1
    dcr d
    jnz rev1
    ret

;    transform cartesian coordinates in the form of x,y
;    to a mask and byte address

cart:    mvi b,016H
    mvi c,004H
    lda wy
    cma
    adi 031H
car1:    cmp b
    jc car2
    sub b
car2:    cmc
    adc a
    dcr c
    jnz car1
    mov c,a
    ani 00FH
    rlc
    rlc
    rlc
    rlc
    sta wye
    mov a,c
    ani 0F0H
    jnz car3
    mvi a,006H
car3:    mov c,a
    ani 026H
    jz car4
    xri 026H
    mov c,a
car4:    lda ex
    dcr a
    mov b,a
    rlc
    ani 0FCH
    sta eks
    mov a,b
    ani 001H
    mov a,c
    jnz car5
    rrc
    rrc
    rrc
car5:    sta msk
    ret

;    draw a line with increments dx,dy = (C,B).  increment
;    may be + or - using complementary arithmetic, but less
;    than 64 in absolute value to avoid overflow problems.

line:    lxi h,ypl
    mov a,b
    ora a
    jp lin1
    cma
    inr a
    mov b,a
    lxi h,ymi
lin1:    lxi d,xpl
    mov a,c
    ora a
    jp lin2
    cma
    inr a
    mov c,a
    lxi d,xmi
lin2:    cmp b
    jnc lin3
    xchg
    mov c,b
    mov b,a
lin3:    mov a,c
    sta wy
    mov a,b
    add a
    mov b,a
    sub c
    push psw
    sub c
    mov c,a
lin4:    pop psw
    push h
    lxi h,culi
    xthl
    cpi 001H
    jm lin5
    push h
    add c
    jmp lin6
lin5:    add b
lin6:    push d
    push psw
    lda ex
    dcr a
    sta ex
    jnz lin4
    pop psw
    ret

;    the movements in one byte necessary to shift the
;    whole screen right one pixel.

expl:    mov a,m
    ani 03FH
    mov b,a
    ani 038H
    rrc
    rrc
    rrc
    ora c
    mov c,a
    mov a,b
    rlc
    rlc
    rlc
    ani 038H
    mov b,c
    mov c,a
    ret

;    the movements within one pixel necessary for shifting
;    the whole screen left one pixel.

exmi:    mov a,m
    ani 03FH
    mov b,a
    rlc
    rlc
    rlc
    ani 038H
    ora c
    mov c,a
    mov a,b
    ani 038H
    rrc
    rrc
    rrc
    mov b,c
    mov c,a
    ret

;    the movements necessary within one byte to shift the
;    whole screen down one pixel.

wymi:    mov a,m
    ani 03FH
    mov b,a
    ani 036H
    rrc
    ora c
    mov c,a
    mov a,b
    rlc
    rlc
    ani 024H
    mov b,c
    mov c,a
    ret

;    the movements necessary within one byte to shift the
;    whole screen up one pixel.

wypl:    mov a,m
    ani 03FH
    mov b,a
    rlc
    ani 036H
    ora c
    mov c,a
    mov a,b
    ani 024H
    rrc
    rrc
    mov b,c
    mov c,a
    ret

;    move the whole screen right one pixel

ekspl:    lxi h,vorg
    lxi d,rsiz-1
eksp1:    push h
    dad d
    call expl
    pop h
eksp2:    call expl
    mov a,b
    ori 080H
    mov m,a
    inx h
    mov a,l
    ani 03FH
    jnz eksp2
    mov a,h
    cpi 0FCH
    jnz eksp1
    ret

;    move the whole screen left one pixel

eksmi:    lxi h,vorg+vsiz-1
    lxi d,-rsiz+1
eksm1:    push h
    dad d
    call exmi
    pop h
eksm2:    call exmi
    mov a,b
    ori 080H
    mov m,a
    mov a,l
    ani 03FH
    dcx h
    jnz eksm2
    mov a,h
    cpi 0F7H
    jnz eksm1
    ret

;    Move the whole screen up one pixel.
;    this is the control loop which calls the shift of
;    a column in such a way as to make it cyclic.

wyepl:    lxi h,vorg+vsiz-1
wyep1:    lxi d,-vsiz+rsiz
    push h
    dad d
    call wypl
    pop h
    push h
    lxi d,-rsiz
wyep2:    call wypl
    mov a,b
    ori 080H
    mov m,a
    dad d
    mov a,h
    cpi 0F7H
    jnz wyep2
    pop h
    mov a,l
    ani 03FH
    dcx h
    jnz wyep1
    ret

;    Move the whole screen down one pixel

wyemi:    lxi h,vorg
wyem1:    lxi d,vsiz-rsiz
    push h
    dad d
    call wymi
    pop h
    push h
    lxi d,rsiz
wyem2:    call wymi
    mov a,b
    ori 080H
    mov m,a
    dad d
    mov a,h
    cpi 0FCH
    jnz wyem2
    pop h
    inx h
    mov a,l
    ani 03FH
    jnz wyem1
    ret

;    Add to the neighbor count of adjoining cells according
;    to the bits in this byte.  We do the middle pixel,
;    adding to the count of three successive neighbors in
;    registers B,C,D.

alfa:    mov a,m
    rrc
    jc alf1
    inr b
    inr c
    inr d
alf1:    rrc
    jc alf2
    inr b
    inr d
alf2:    rrc
    rc
    inr b
    inr c
    inr d
    ret

;    shift the neighbor count as we move forward one byte in
;    a row scan

beta:    mov b,c
    mov c,d
    mvi d,00H
    inx h
    mov a,l
    ani 03FH
    rnz
    push d
    lxi d,-rsiz
    dad d
    pop d
    ret

;    PRINCIPAL PROGRAM for carrying out a cycle of LIFE.
;    Only the middle pixel in each byte is calculated
;    so that three passes are necessary after each of three
;    shifts. Two adjacent pixels are used, the right to hold
;    the present living status and the left for information
;    for the next cycle.

epsi:    lxi h,vorg+rsiz-1
gama:    mvi d,00H
    call alfa
    call beta
    call alfa
delt:    push h
    call beta
    call alfa
    xthl
    mov a,b
    cpi 002H
    jz eta
    cpi 003H
    jz zeta
    mov a,m
    ori 010H
    mov m,a
    jmp thet
zeta:    mov a,m
    ani 0EFH
    mov m,a
    jmp thet
eta:    mov a,m
    ani 0EFH
    mov e,a
    ani 002H
    rlc
    rlc
    rlc
    ora e
    mov m,a
thet:    pop h
    mov a,l
    ani 03FH
    jnz delt
    push d
    lxi d,007FH
    dad d
    pop d
    mov a,h
    cpi 0FCH
    jnz gama
    ret

;    updating loop, moving left pixel to right

cycl:    lxi h,vorg
cyc1:    mov a,m
    ani 038H
    mov b,a
    rrc
    rrc
    rrc
    ora b
    ori 080H
    mov m,a
    inx h
    mov a,h
    cpi 0FCH
    jnz cyc1
    ret

;    execute a single cycle of LIFE by updating the middle
;    pixel and making three sweeps after shifting each time

hh:    call epsi
    call wyepl
    call epsi
    call wyepl
    call epsi
    call wyemi
    call wyemi
    call cycl
    ret

;    repeat h unless an ASCII character is waiting
;    (version for VDM using port ED)

gg:    in  0EDH
    ani 040H
    rnz
    call hh
    jmp  gg

;    version for POLY-88 using keyboard flag at 0C0CH

ge:    lda 0C0CH
    ora a
    rz
    call hh
    jmp ge

;    extinguish cursor, move two pixels east, light cursor

ee:    call crev
    call xpl
    call xpl
    jmp  crev

;    extinguish cursor, two pixels west, light cursor

ww:    call crev
    call xmi
    call xmi
    jmp  crev

;    extinguish cursor, one pixel north, light cursor

nn:    call crev
    call ypl
    jmp  crev

;    extinguish cursor, one pixel south, light cursor

ss:    call crev
    call ymi
    jmp  crev

;    extinguish a life cell

kk:    call xpl
    call cuex
    jmp xmi

;    activate a life cell

ll:    call xpl
    call culi
    jmp  xmi

;    move whole screen right one life cell, with cursor

eas:    call ekspl
    call ekspl
    call xpl
    jmp  xpl

;    move the whole screen left one life cell, with cursor

wes:    call eksmi
    call eksmi
    call xmi
    jmp  xmi

;    move the whole screen up one life cell, with cursor

nor:    call wyepl
    jmp  ypl

;    move the whole screen down one life cell, with cursor

sou:    call wyemi
    jmp  ymi

;    directory vector for LIFE demonstration

vect:    cpi 'N'
    jz  nor
    cpi 'S'
    jz  sou
    cpi 'E'
    jz  eas
    cpi 'W'
    jz  wes
    cpi 06EH
    jz  nn
    cpi 073H
    jz  ss
    cpi 065H
    jz  ee
    cpi 077H
    jz  ww
    cpi 06BH
    jz  kk
    cpi 06CH
    jz  ll
    cpi 063H
    jz  blak
    cpi 072H
    jz  reve
    cpi 068H
    jz  hh
    cpi 067H
    jz  go
    cpi '.'
    jz  crev
    cpi ';'
    jz  0000H
    ret

;    keyboard read routine

read:    in  0EDH
    ani 040H
    jz   read
    in  0EFH
    ani 07FH
    ret

;    MAIN PROGRAM for LIFE demonstration

main:    call blak
    call home
    call crev
here:    lxi h,here
    push h
    call chin
    jmp  vect

    end