terminal emulator experiments.

This commit is contained in:
Kelvin Sherlock 2021-04-04 20:22:43 -04:00
commit 2efe25fdb9
6 changed files with 1113 additions and 0 deletions

100
boot.S Normal file
View File

@ -0,0 +1,100 @@
*
* boot block.
*
* loaded at $0800
xc
xc
rel
SLOT equ $00
CMD equ $42
UNIT equ $43
BUFFER equ $44
BLOCK equ $46
ext init
boot
mx %11
db $01 ; prodos boot id
* slot 5 = x = $50, a = $3178
* slot 6 = x = $60, a = $8401
* stx :unit
* txa
* lsr
* lsr
* lsr
* lsr
* ora #$c0
stx UNIT
txa
lsr
lsr
lsr
lsr
ora #$c0
sta :prodos+2
stz SLOT
sta SLOT+1
ldy #1
lda (SLOT),y
cmp #$20
bne noboot
ldy #3
lda (SLOT),y
bne noboot
ldy #5
lda (SLOT),y
cmp #$03
bne noboot
ldy #$ff
lda (SLOT),y
sta :prodos+1
lda #1
sta CMD
sta BLOCK
stz BLOCK+1
stz BUFFER
lda #$a0 ; $0800+512
sta BUFFER+1
:read
jsr :prodos ; block 1
bcs noboot
inc BLOCK
inc BUFFER+1
inc BUFFER+1
lda BLOCK
cmp #6
bcc :read
bra :ok
:prodos jmp $0000
:ok
clc
xce
cli
jsr init
noboot
:loop wai
bra :loop
sav boot.L

21
link.S Normal file
View File

@ -0,0 +1,21 @@
* binary link
lkv 0
org $0800
ovr all
* if boot.S
asm boot.S
* if vt52.S
asm vt52.S
lnk boot.L
lnk vt52.L
pos eof
sav vt52.bin
ent
end

24
makefile Normal file
View File

@ -0,0 +1,24 @@
scc.po: scc.bin
dd bs=1024 count=800 if=/dev/zero of=scc.po
dd bs=512 if=scc.bin of=scc.po conv=notrunc
modem.po: modem.bin
dd bs=1024 count=800 if=/dev/zero of=modem.po
dd bs=512 if=modem.bin of=modem.po conv=notrunc
vt52.po: vt52.bin
dd bs=1024 count=800 if=/dev/zero of=vt52.po
dd bs=512 if=vt52.bin of=vt52.po conv=notrunc
vt52.bin: vt52.S boot.S link.S
iix qlink link.S
scc.bin: scc.s
iix qasm scc.s
modem.bin: modem.s
iix qasm modem.s

237
modem.s Normal file
View File

@ -0,0 +1,237 @@
lst off
exp off
*
* read modem port
*
*
cmdb equ $c038
cmda equ $c039
datab equ $c03a
dataa equ $c03b
cout equ $fded
read mac
ldx #]1
if 3=]1
stx cmda
lda cmda
else
stx cmdb
lda cmdb
fin
sta buffer,x
<<<
lst on
org $0800
mx %11
db $01 ; prodos boot id
boot
* clc
* xce
* cli
sei
ldx #24
lda #$80+$0d
:cs jsr cout
dex
bpl :cs
* just in case.
lda cmdb
lda cmdb
init
* reset channel b
ldx #9
lda #%01010001
stx cmdb
sta cmdb
nop
nop
* x16 clock mode, 1 stop bit, no parity
ldx #4
lda #%01000100
stx cmdb
sta cmdb
* 8 bits/char, rx disabled.
ldx #3
lda #%11000000
stx cmdb
sta cmdb
* 8 data bits, RTS
ldx #5
lda #%01100010
stx cmdb
sta cmdb
ldx #11
lda #%01010000
stx cmdb
sta cmdb
* 9600 baud
ldx #12
lda #10
stx cmdb
sta cmdb
* 9600 baud
ldx #13
lda #0
stx cmdb
sta cmdb
* disable baud rate generator
ldx #14
lda #0
stx cmdb
sta cmdb
* enable baud rate generator
ldx #14
lda #%00000001
stx cmdb
sta cmdb
* 8 bits/char, rx enabled.
ldx #3
lda #%11000001
stx cmdb
sta cmdb
* 8 data bits, tx enabled, RTS
ldx #5
lda #%01101010
stx cmdb
sta cmdb
* disable interrupts
ldx #15
lda #0
stx cmdb
sta cmdb
* reset ext/status interrupts
ldx #0
lda #%00010000
stx cmdb
sta cmdb
* disable interrupts
ldx #1
lda #0
stx cmdb
sta cmdb
* reset ch b ptr to 0?
lda cmdb
* status, visible, master interrupts disabled
ldx #9
lda #%00010001
stx cmdb
sta cmdb
nop
nop
* read registers - 0, 1, 2, 3, 8, 10, 12, 13, 15
* 3 is channel A only.
loop
read 0
read 1
read 2
read 3
read 8
read 10
read 12
read 13
read 15
ldx #15
:cmp lda buffer,x
cmp prev,x
bne :delta
dex
bpl :cmp
bra wailoop
:delta
ldx #0
:print
lda buffer,x
phx
pha
lsr
lsr
lsr
lsr
tax
lda hex,x
jsr cout
pla
and #$0f
tax
lda hex,x
jsr cout
lda #" "
jsr cout
plx
inx
cpx #16
bcc :print
lda #$80+$0d
jsr cout
* store prev. values.
ldx #15
:copy lda buffer,x
sta prev,x
dex
bpl :copy
wailoop
* wai
brl loop
nop
nop
stp
hex asc "0123456789abcdef"
buffer ds 16
prev ds 16
lst off
* ds \
ds 1024+$0800-*
sav modem.bin

142
scc.s Normal file
View File

@ -0,0 +1,142 @@
lst off
exp off
*
* read slot 7 ssc card.
*
*
cmdb equ $c038
cmda equ $c039
datab equ $c03a
dataa equ $c03b
cout equ $fded
read mac
ldx #]1
if 3=]1
stx cmda
lda cmda
else
stx cmdb
lda cmdb
fin
sta buffer,x
<<<
lst on
org $0800
mx %11
db $01 ; prodos boot id
boot
* clc
* xce
* cli
sei
ldx #24
lda #$80+$0d
:cs jsr cout
dex
bpl :cs
SSC equ $c088+$70
init
* command register - DTR+, IRQ-, TX IRQ-, ECHO-, PARITY-
lda #%0000_1011
sta SSC+2
*control - 9600, BRG, /1
lda #%0_00_1_1110
sta SSC+3
* read 4 registers
loop
; status first
lda SSC+1
sta buffer+1
lda SSC+0
sta buffer+0
lda SSC+2
sta buffer+2
lda SSC+3
sta buffer+3
ldx #3
:cmp lda buffer,x
cmp prev,x
bne :delta
dex
bpl :cmp
bra wailoop
:delta
ldx #0
:print
lda buffer,x
phx
pha
lsr
lsr
lsr
lsr
tax
lda hex,x
jsr cout
pla
and #$0f
tax
lda hex,x
jsr cout
lda #" "
jsr cout
plx
inx
cpx #4
bcc :print
lda #$80+$0d
jsr cout
* store prev. values.
ldx #3
:copy lda buffer,x
sta prev,x
dex
bpl :copy
wailoop
* wai
brl loop
nop
nop
stp
hex asc "0123456789abcdef"
buffer ds 16
prev ds 16
lst off
* ds \
ds 1024+$0800-*
sav scc.bin

589
vt52.S Normal file
View File

@ -0,0 +1,589 @@
lst off
xc
xc
rel
* vt52 emulator.
* not supported - graphics, screen hold.
*
*
*
*
SET80VID equ $c00d
SETALTCHAR equ $c00f
TXTSET equ $c051
ent init
dum 0
text00 adrl 0
text01 adrl 0
state dw 0
mode dw 0
x dw 0
y dw 0
* cursor
cursor_ptr adrl 0
cursor_saved_char dw 0
cursor_state dw 0
dend
init
sep #$30
sta TXTSET
sta SET80VID
sta SETALTCHAR
rep #$30
stz x
stz y
stz mode
stz state
lda #$0400
sta text00
stz text00+2
sta text01
lda #$0001
sta text01+2
jmp clear_all
cc mac
ldx #38
]loop sta ]1,x
stal $010000+]1,x
dex
dex
bpl ]loop
<<<
cp mac
ldx #38
]loop lda ]1,x
sta ]2,x
ldal $010000+]1,x
stal $010000+]2,x
dex
dex
bpl ]loop
<<<
clear_eol
sep #$20
lda x
lsr
tay
lda #" "
bcc :even
sta [text01],y
iny
:even
cpy #80/2
bcs :rts
sta (text00),y
sta [text01],y
iny
cpy #40
bra :even
:rts rep #$20
rts
clear_eos
lda x
ora y
beq clear_all
lda x
beq :x0
jsr clear_eol
lda y
inc
bra :x1
:x0
lda y
:x1 cmp #23
bcs :rts
asl
tax
lda #" "
jmp (clear_table,x)
:rts rts
clear_all
lda #" " ; high bit
c00 cc $0400
c01 cc $0480
c02 cc $0500
c03 cc $0580
c04 cc $0600
c05 cc $0680
c06 cc $0700
c07 cc $0780
c08 cc $0428
c09 cc $04a8
c10 cc $0528
c11 cc $05a8
c12 cc $0628
c13 cc $06a8
c14 cc $0728
c15 cc $07a8
c16 cc $0450
c17 cc $04d0
c18 cc $0550
c19 cc $05d0
c20 cc $0650
c21 cc $06d0
c22 cc $0750
c23 cc $07d0
rts
clear_table
dw c00,c01,c02,c03,c04,c05,c06,c07,c08,c09
dw c10,c11,c12,c13,c14,c15,c16,c17,c18,c19
dw c20,c21,c22,c23
scroll_up
cp $0480;$0400
cp $0500;$0480
cp $0580;$0500
cp $0600;$0580
cp $0680;$0600
cp $0700;$0680
cp $0780;$0700
cp $0428;$0780
cp $04a8;$0428
cp $0528;$04a8
cp $05a8;$0528
cp $0628;$05a8
cp $06a8;$0628
cp $0728;$06a8
cp $07a8;$0728
cp $0450;$07a8
cp $04d0;$0450
cp $0550;$04d0
cp $05d0;$0550
cp $0650;$05d0
cp $06d0;$0650
cp $0750;$06d0
cp $07d0;$0750
lda #" "
cc $07d0
rts
scroll_down
cp $0750;$07d0
cp $06d0;$0750
cp $0650;$06d0
cp $05d0;$0650
cp $0550;$05d0
cp $04d0;$0550
cp $0450;$04d0
cp $07a8;$0450
cp $0728;$07a8
cp $06a8;$0728
cp $0628;$06a8
cp $05a8;$0628
cp $0528;$05a8
cp $04a8;$0528
cp $0428;$04a8
cp $0780;$0428
cp $0700;$0780
cp $0680;$0700
cp $0600;$0680
cp $0580;$0600
cp $0500;$0580
cp $0480;$0500
cp $0400;$0480
lda #" "
cc $0400
rts
draw_char
; a = char to draw
ora #$80
tax
lda y
lsr
tay
txa
bcs :x1
sep #$20
sta (text00),y
rep #$20
inc x
jmp update_cursor
:x1
sep #$20
sta [text01],y
rep #$20
lda x
cmp #79
bcs :rts
inc x
:rts jmp update_cursor
text
dw $0400
dw $0480
dw $0500
dw $0580
dw $0600
dw $0680
dw $0700
dw $0780
dw $0428
dw $04a8
dw $0528
dw $05a8
dw $0628
dw $06a8
dw $0728
dw $07a8
dw $0450
dw $04d0
dw $0550
dw $05d0
dw $0650
dw $06d0
dw $0750
dw $07d0
* based on testing, control handling happens first. ESC within an ESC Y sequence resets to ESC state.
vt52
cmp #' '
bcs :normal
asl
tax
jmp (ctrl_table,x)
:normal
ldx state
jmp (st_table,x)
st_table
dw state_0,state_1,state_2,state_3
state_0
and #$7f
cmp #$7f
beq :rts
jsr draw_char
:rts
rts
state_1 ; ESC encountered
:MIN equ '<'
:MAX equ '\'
stz state
and #$7f
cmp #:MIN
bcc :rts
cmp #:MAX+1
bcs :rts
sec
sbc #:MIN
asl
tax
jmp (:table,x)
:rts
rts
:table
dw esc_lt ; <
dw esc_eq ; =
dw esc_gt ; >
dw :rts ; ?
dw :rts ; @
dw esc_A ; A
dw esc_B ; B
dw esc_C ; C
dw esc_D ; D
dw :rts ; E
dw esc_F ; F
dw esc_G ; G
dw esc_H ; H
dw esc_I ; I
dw esc_J ; J
dw esc_K ; K
dw :rts ; L
dw :rts ; M
dw :rts ; N
dw :rts ; O
dw :rts ; P
dw :rts ; Q
dw :rts ; R
dw :rts ; S
dw :rts ; T
dw :rts ; U
dw :rts ; V
dw :rts ; W
dw :rts ; X
dw esc_Y ; Y
dw esc_Z ; Z
dw esc_[ ; [
dw esc_\ ; \
state_2 ; ESC Y encountered, part 1
* out of bounds line is ignored.
inc state
inc state
and #$7f
sec
sbc #' '
cmp #24
bcs :rts
sta y
jmp update_cursor
:rts rts
state_3 ; ESC Y encountered, part 2
* out of bounds column is ignored.
* vt52 doc claims it moves to the rightmost column but this
* doesn't reflect actual behavior.
stz state
and #$7f
sec
sbc #' '
cmp #80
bcs :rts
sta x
jmp update_cursor
:rts rts
ctrl_table
dw ctrl_00,ctrl_01,ctrl_02,ctrl_03
dw ctrl_04,ctrl_05,ctrl_06,ctrl_07
dw ctrl_08,ctrl_09,ctrl_0a,ctrl_0b
dw ctrl_0c,ctrl_0d,ctrl_0e,ctrl_0f
dw ctrl_10,ctrl_11,ctrl_12,ctrl_13
dw ctrl_14,ctrl_15,ctrl_16,ctrl_17
dw ctrl_18,ctrl_19,ctrl_1a,ctrl_1b
dw ctrl_1c,ctrl_1d,ctrl_1e,ctrl_1f
ctrl_00
ctrl_01
ctrl_02
ctrl_03
ctrl_04
ctrl_05
ctrl_06
ctrl_0b
ctrl_0c
ctrl_0e
ctrl_0f
ctrl_10
ctrl_11
ctrl_12
ctrl_13
ctrl_14
ctrl_15
ctrl_16
ctrl_17
ctrl_18
ctrl_19
ctrl_1a
ctrl_1c
ctrl_1d
ctrl_1e
ctrl_1f
rts
ctrl_07 ; ring the bell.
rts
ctrl_1b ; escape -
lda #2
sta state
rts
ctrl_09 ; tab
lda x
cmp #73
bcs :one
clc
adc #8
and #$07!$ff
sta x
bra :update
:one
cmp #79
bcs :rts
inc x
:update
jmp update_cursor
:rts rts
ctrl_0a ; line feed - cursor down w/ scroll
lda y
cmp #23
blt :simple
jmp scroll_down
:simple
iny
jmp update_cursor
ctrl_0d ; carriage return - cursor to column 0.
stz x
jmp update_cursor
esc_A ; cursor up w/o scroll
lda y
beq :rts
dec y
jmp update_cursor
:rts rts
esc_B ; cursor down w/o scroll
lda y
inc
cmp #24
bcs :rts
inc y
jmp update_cursor
:rts rts
esc_C ; cursor right w/o wrap
lda x
inc
cmp #79
bcs :rts
inc x
jmp update_cursor
:rts rts
esc_D ; cursor left w/o wrap
ctrl_08 ; back space - cursor left w/o wrap
lda x
beq :rts
dec x
jmp update_cursor
:rts rts
esc_F ; enter graphics mode
lda #%0010
tsb mode
rts
esc_G ; exit graphics mode
lda #%0010
trb mode
rts
esc_H ; cursor home
stz x
stz y
jmp update_cursor
esc_I ; reverse line feed - cursor up w/ scroll
lda y
bne :simple
jmp scroll_up
:simple
dec y
jmp update_cursor
esc_J ; erase to end of screen
jmp clear_eos
esc_K ; erase to end-of-line
jmp clear_eol
esc_Y ; direct cursor addressing
lda #4
sta state
rts
esc_Z ; identify terminal.
; return ESC / K
rts
esc_[ ; enter hold screen mode
lda #%0100
tsb mode
rts
esc_\ ; exit hold screen mode
lda #%0100
trb mode
rts
esc_eq ; enter alternate keypad mode
lda #%0001
tsb mode
rts
esc_gt ; exit alternate keypad mode
lda #%0001
trb mode
rts
esc_lt ; vt100 - enter ANSI mode (exit vt52 mode).
rts
update_cursor
rts
* lst on
* sym on
sav vt52.L