C64U UCI HTTP BASIC EXAMPLE

BASIC program example for the C64U (Commodore 64 Ultimate) interface that demonstrates how to perform an HTTP GET request. The code constructs a request to httpbin.org, opens a TCP connection, sends the request, and reads the JSON response body. It includes subroutines for locating the UCI (Ultimate Command Interface) hardware, mapping PETSCII characters to ASCII, and handling network communication errors.

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Learn more about bidirectional Unicode characters Show hidden characters 10 rem c64u uci http query tester v1.6 20 print chr$ 147 :poke646,1:print "c64u uci http qry v1.6" 30 rem c is command bytes, d is uci reply bytes 40 dim c 260 ,d 260 :dc=260 50 rem endpoint pieces: httpbin echoes query in json args 60 hn$="httpbin.org":qp$="codex=basic&uci=1" 70 pa$="/get?"+qp$:ag$="c64u-basic/1.0" 80 rem find uci, identify network target, open tcp 90 gosub 1000:if er then end 100 co=3:m$="uci base "+str$ ba :gosub 900 110 co=7:m$="identify network":gosub 900 120 c 0 =3:c 1 =1:cl=2:gosub 3000 130 if er then co=2:m$="identify failed "+s$:gosub 900:end 140 co=5:m$="network target ok":gosub 900 150 co=7:m$="open tcp "+hn$+":80":gosub 900 160 c 0 =3:c 1 =7:c 2 =80:c 3 =0:cl=4 170 q$=hn$+chr$ 0 :gosub 2000 180 gosub 3000 190 if er then co=2:m$="open failed "+s$:gosub 900:end 200 if dl<1 then co=2:m$="no socket id":gosub 900:end 210 so=d 0 :co=5:m$="socket "+str$ so :gosub 900 220 rem build readable http request from strings 230 co=7:m$="build http request":gosub 900 240 rq$="GET "+pa$+" HTTP/1.1"+chr$ 13 +chr$ 10 250 rq$=rq$+"Host: "+hn$+chr$ 13 +chr$ 10 260 rq$=rq$+"User-Agent: "+ag$+chr$ 13 +chr$ 10 270 rq$=rq$+"Accept: / "+chr$ 13 +chr$ 10 280 rq$=rq$+"Connection: close"+chr$ 13 +chr$ 10 +chr$ 13 +chr$ 10 290 rem write socket command: target 3, command 17, socket, payload 300 co=7:m$="send http request":gosub 900 310 c 0 =3:c 1 =17:c 2 =so:cl=3 320 q$=rq$:gosub 2000:wr=cl-3 330 gosub 3000 340 if er then co=2:m$="write failed "+s$:gosub 900:gosub 7000:end 350 if dl<2 then co=2:m$="write reply short":gosub 900:gosub 7000:end 360 ac=d 0 +256 d 1 370 if ac<wr then co=2:m$="short write "+str$ ac :gosub 900:gosub 7000:end 380 co=5:m$="request sent":gosub 900 390 rem read response in chunks and print only body 400 co=7:m$="read response":gosub 900 410 poke646,1:print "---- json body ----" 420 hd=0:hm=0:bt=0:id=0:rc=0 430 c 0 =3:c 1 =16:c 2 =so:c 3 =128:c 4 =0:cl=5 440 gosub 3000 450 if er and left$ s$,2 ="02" then id=id+1:goto 530 460 if er and left$ s$,2 ="01" then goto 570 470 if er then co=2:m$="read failed "+s$:gosub 900:gosub 7000:end 480 if dl<2 then id=id+1:goto 530 490 ac=d 0 +256 d 1 500 if ac=0 then id=id+1:goto 530 510 id=0:rc=rc+ac 520 for i=2 to ac+1:x=d i :gosub 5000:next i 530 if id<60 and rc<4096 then goto 430 540 if rc=0 then co=2:m$="no response":gosub 900:gosub 7000:end 550 if id =60 then co=2:m$="read timeout":gosub 900:gosub 7000:end 560 goto 580 570 co=5:m$="closed by host":gosub 900 580 gosub 7000 590 co=5:m$="done bytes "+str$ rc :gosub 900 600 poke646,1:end 890 rem sub 900: print m$ using color co for progress/fail status 900 poke646,co:print m$:return 990 rem sub 1000: locate ultimate command interface base register 1000 er=0:ba=57116 1010 if peek ba+1 =201 then gosub 1100:return 1020 ba=56860 1030 if peek ba+1 =201 then gosub 1100:return 1040 ba=57340 1050 if peek ba+1 =201 then gosub 1100:return 1060 co=2:m$="uci not enabled":gosub 900 1070 er=1:return 1090 rem sub 1100: derive uci register addresses from base ba 1100 cs=ba:cd=ba+1:rd=ba+2:sd=ba+3:return 1990 rem sub 2000: append q$ to c after petscii-to-ascii mapping 2000 for i=1 to len q$ 2010 x=asc mid$ q$,i,1 :gosub 2200 2020 c cl =x:cl=cl+1:next i:return 2190 rem sub 2200: map one basic string byte x to network wire ascii 2200 if x=13 or x=10 or x=9 or x=0 then return 2210 if x =193 and x<=218 then x=x-128:return 2220 if x =65 and x<=90 then x=x+32:return 2230 if x =97 and x<=122 then return 2240 if x =32 and x<=126 then return 2250 x=63:return 2990 rem sub 3000: send c command, collect d reply and s$ status 3000 er=0:dl=0:sl=0:s$="" 3010 gosub 3400:if er then return 3020 for i=0 to cl-1:poke cd,c i :next i 3030 poke cs,1 3040 for w=1 to 20000 3050 zt=peek cs 3060 if zt and 128 < 0 then x=peek rd :if dl<dc then d dl =x:dl=dl+1 3070 if zt and 128 < 0 then goto 3050 3080 if zt and 64 < 0 then x=peek sd :if sl<240 then s$=s$+chr$ x :sl=sl+1 3090 if zt and 64 < 0 then goto 3050 3100 ss=zt and 48 3110 if zt and 8 < 0 then poke cs,8:er=1:s$="uci error":return 3120 if zt and 4 < 0 then poke cs,4:goto 3050 3130 if ss=32 or ss=48 then poke cs,2:goto 3050 3140 if ss=0 and zt and 1 =0 then goto 3180 3150 next w 3160 er=1:s$="uci timeout":return 3180 if sl<2 then er=1:s$="no status":return 3190 if left$ s$,2 < "00" then er=1 3200 return 3390 rem sub 3400: drain old uci data/status and wait for idle 3400 for w=1 to 20000 3410 zt=peek cs 3420 if zt and 128 < 0 then x=peek rd :goto 3410 3430 if zt and 64 < 0 then x=peek sd :goto 3410 3440 ss=zt and 48 3450 if zt and 8 < 0 then poke cs,8:goto 3410 3460 if zt and 4 < 0 then poke cs,4:goto 3410 3470 if ss=32 or ss=48 then poke cs,2:goto 3410 3480 if ss=0 and zt and 1 =0 then return 3490 next w 3500 er=1:s$="sync timeout":return 4990 rem sub 5000: skip http headers until cr/lf/cr/lf, then body 5000 if hd=1 then gosub 6000:return 5010 if hm=0 and x=13 then hm=1:return 5020 if hm=1 and x=10 then hm=2:return 5030 if hm=2 and x=13 then hm=3:return 5040 if hm=3 and x=10 then hd=1:print "httpbin /get? json:":return 5050 if x=13 then hm=1:return 5060 hm=0:return 5990 rem sub 6000: print one body byte in readable c64 text 6000 if x=13 then return 6010 if x=10 then print:return 6020 if x=9 then print " ";:return 6030 if x=123 or x=91 then print:print " ";:bt=bt+1:return 6040 if x=125 or x=93 then print:print " ";:bt=bt+1:return 6050 if x=92 then print "/";:bt=bt+1:return 6060 if x=44 then print ",":return 6070 if x =97 and x<=122 then x=x-32 6080 if x =32 and x<=95 then print chr$ x ;:bt=bt+1:return 6090 print ".";:bt=bt+1:return 6990 rem sub 7000: close tcp socket through uci network target 7000 c 0 =3:c 1 =9:c 2 =so:cl=3:gosub 3000:return