View source for Commodore64 VT100 Emulator

{{Project
|ProjectName=Commodore64 VT100 Emulator
|Owner=Peterbjornx
|Skillz=BASIC, 6502 Asm
|Status=Active
|Summary=I'm writing a VT100 emulator for the C64.
}}
Current code (BasEdit preprocessor needed):
 <nowiki>
goto test
asciiputchar:
rem asciiputchar
if c<5 then return
if c=6 then return

if c<>5 goto not5
if xc=1 then print# tf,ab$;
if xc=0 then bc$=bc$+ab$
return

not5:
if c<>7 goto not7
gosub bell
return

not7:
if c<>8 goto not8
gosub backspace
return

not8:
if c<>9 goto not9
gosub horiztab
return

not9:
if c<>10 goto not10
gosub linefeed
return

not10:
if c<>11 goto not11
gosub linefeed
return

not11:
if c<>12 goto not12
gosub linefeed
return

not12:
if c<>13 goto not13
gosub carriagereturn
return

not13:
if c<>14 goto not14
cs=g1
return

not14:
if c<>15 goto not15
cs=g0
return

not15:
if c=16 then return
if c<>17 goto not17
xc=1
print# tf,bc$
bc$=""
return

not17:
if c=18 then return
if c<>19 goto not19
xc=0
bc$=""
return

not19:
if c<32 then return
if c<65 goto endfunc
if c=91 goto endfunc
if c<>92 goto not92
c=191
goto endfunc

not92:
if c=93 goto endfunc
if c=94 goto endfunc
if c<>95 goto not95
c=164
goto endfunc

not95:
if c<>96 goto not96
c=189
goto endfunc

not96:
if c<>123 goto not123
c=179
goto endfunc

not123:
if c<>124 goto not124
c=125
goto endfunc

not124:
if c<>125 goto not125
c=171
goto endfunc

not125:
if c<>126 goto not126
c=163
goto endfunc

not126:
if c=127 then return
if c<91 goto uppercase
if c<123 goto lowercase
print# of,chr$(28)+chr$(94)+chr$(fc);
gosub pollcursor
return

lowercase:
c=c-32
goto endfunc

uppercase:
c=c+32
goto endfunc

endfunc:
print# of,chr$(c);
gosub pollcursor
return

bell:
rem bell
poke 54276,17
for t=1 to 500: next
poke 54276,16
return

backspace:
rem backspace
cx=cx-1
if cx<0 then cx=0
gosub setcursor
return

horiztab:
rem horizontal tab
ox=cx
cx=cx-(INT(cx/ts)*ts)
if cx<ox then cx=cx+ts
if cx>39 then cx=39
gosub setcursor
return

linefeed:
rem line feed
if nl=1 goto newline
print# of, chr$(17)
gosub pollcursor
return

newline:
print# of, chr$(12)
gosub pollcursor
return

carriagereturn:
rem carriage return
cx=0
gosub setcursor
return

pollcursor:
rem pollcursor
cx=peek(211)
cy=peek(214)
return 

setcursor:
rem setcursor
poke 211,cx
poke 214,cy
return

initbell:
rem initbell
for l=54272 to 54296: poke l,0:next
poke 54296,15
poke 54277,33
poke 54278,129
poke 54272,135
poke 54273,33
return

initscreen:
rem initscreen
open of,3,0
print# of, chr$(9);
print# of, chr$(147);
return

initout:
rem initout
xc=1
bc$=""
fc=31
cx=0
cy=0
g0=0
g1=1
cs=g0
nl=1
ts=8
ab$="answerback"
return

init:
rem init
of=3
gosub initout
gosub initbell
gosub initscreen
gosub initser
return

initser:
rem initser
tf=2
open tf,2,0,chr$(6)
return

test:
rem test
gosub init
testloop:
get# tf,c$
if len(c)=0 goto testloop
c=asc(c$)
gosub asciiputchar
goto testloop

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