# The 56k dial-up handshake, for one RouterOS beeper
# https://lab.glossema.dev/play/dial-up
# Timed off William Termini's iMac G3 recording (2008), as Oona Raisanen charted it
# in "The sound of the dialup, pictured" (windytan.com, 2012). Signals per ITU-T
# V.8bis, V.8, V.21, V.34 and V.90. About 27 seconds; needs a RouterOS with :timestamp.

{
  :local t0 [:tonsec [:timestamp]];
  :local hold 60ms;

  # Every wait sleeps in 10ms steps and stops 10ms before its mark, so an
  # event lands within about 10ms either side of its time. No wait ever spins
  # without a :delay, so an emulator whose clock only moves on :delay still
  # finishes.

  # One steady tone from start to stop (ms on the recording's clock). tail
  # lets it ring on into whatever follows at once, 0 before a silence.
  :local tone do={
    :local a [:tonum $start];
    :local b [:tonum $stop];
    :while ((([:tonsec [:timestamp]] - $t0) / 1000000) < ($a - 10)) do={ :delay 10ms; }
    :local left ($b - (([:tonsec [:timestamp]] - $t0) / 1000000));
    :if ($left > 0) do={ :beep frequency=[:tonum $hz] length=(1ms * ($left + [:tonum $tail])); }
    :while ((([:tonsec [:timestamp]] - $t0) / 1000000) < ($b - 10)) do={ :delay 10ms; }
  };

  # Several signals at once, taken in turn, one per step. A voice is a fixed
  # tone "1800", a random pick of two "980|1180" (FSK bits), or anywhere in a
  # band "800~1600". tail: how long the last beep may ring - short before a
  # silence, longer when the next section follows straight on.
  :local mix do={
    :local lo [:toarray ""];
    :local sp [:toarray ""];
    :local kd [:toarray ""];
    :foreach e in=[:toarray $voices] do={
      :local v [:tostr $e];
      :local r [:find $v "~"];
      :local c [:find $v "|"];
      :local k 0;
      :local x $v;
      :local y $v;
      :if ([:typeof $r] = "num") do={ :set k 1; :set x [:pick $v 0 $r]; :set y [:pick $v ($r + 1) [:len $v]]; }
      :if ([:typeof $c] = "num") do={ :set k 2; :set x [:pick $v 0 $c]; :set y [:pick $v ($c + 1) [:len $v]]; }
      :set lo ($lo, [:tonum $x]);
      :set sp ($sp, ([:tonum $y] - [:tonum $x]));
      :set kd ($kd, $k);
    }
    :local n [:len $lo];
    :local s [:tonum $seed];
    :local i 0;
    :local f ($lo->0);
    :local a [:tonum $start];
    :local b [:tonum $stop];
    :while ((([:tonsec [:timestamp]] - $t0) / 1000000) < ($a - 10)) do={ :delay 10ms; }
    :while ((([:tonsec [:timestamp]] - $t0) / 1000000) < $b) do={
      :local j ($i % $n);
      :set s ((75 * $s) % 65537);
      :set f ($lo->$j);
      :if (($kd->$j) = 1) do={ :set f ($f + ($s % ($sp->$j))); }
      :if (($kd->$j) = 2) do={ :set f ($f + (($s % 2) * ($sp->$j))); }
      :beep frequency=$f length=$hold;
      :delay 10ms;
      :set i ($i + 1);
    }
    :beep frequency=$f length=(1ms * [:tonum $tail]);
  };

  # A low buzz, re-struck every period ms with a one-step accent - the DIL's
  # flutter.
  :local buzz do={
    :local a [:tonum $start];
    :local b [:tonum $stop];
    :local p [:tonum $period];
    :while ((([:tonsec [:timestamp]] - $t0) / 1000000) < ($a - 10)) do={ :delay 10ms; }
    :local nx $a;
    :while ($nx < $b) do={
      :beep frequency=[:tonum $accent] length=$hold;
      :delay 10ms;
      :beep frequency=[:tonum $hz] length=(1ms * ($p + 40));
      :set nx ($nx + $p);
      :if ($nx > $b) do={ :set nx $b; }
      :while ((([:tonsec [:timestamp]] - $t0) / 1000000) < ($nx - 10)) do={ :delay 10ms; }
    }
  };

  # DTMF keypad, and the seven digits dialed in the recording.
  :local row {"k1"=697; "k2"=697; "k3"=697; "k4"=770; "k5"=770; "k6"=770; "k7"=852; "k8"=852; "k9"=852; "k*"=941; "k0"=941; "k#"=941};
  :local col {"k1"=1209; "k4"=1209; "k7"=1209; "k*"=1209; "k2"=1336; "k5"=1336; "k8"=1336; "k0"=1336; "k3"=1477; "k6"=1477; "k9"=1477; "k#"=1477};
  :local number "3440208";

  # 0.0 s - off hook. The copy starts partway into the dial tone.
  :put "Dial tone - 350 + 440 Hz";
  $mix t0=$t0 hold=$hold start=0 stop=500 voices="350,440" seed=1 tail=10;

  # 0.5 s - a digit every 168ms, 115ms of row and column tone together.
  :put "Dialing";
  :for i from=0 to=([:len $number] - 1) do={
    :local d ("k" . [:pick $number $i]);
    :local ds (507 + (168 * $i));
    $mix t0=$t0 hold=$hold start=$ds stop=($ds + 115) voices=(($row->$d) . "," . ($col->$d)) seed=($i + 2) tail=10;
  }

  # 2.6 s - one crackle on the line, then a second of nothing.
  $mix t0=$t0 hold=$hold start=2574 stop=2659 voices="150~700,1800~3700" seed=11 tail=10;

  # 3.6 s - V.8bis. Tone pair + tag, then 300 baud messages both ways.
  :put "V.8bis - CRe: 1375 + 2002 Hz, then 400 Hz";
  $mix t0=$t0 hold=$hold start=3631 stop=3913 voices="1375,2002" seed=12 tail=40;
  $tone t0=$t0 start=3913 stop=4012 hz=400 tail=40;
  $tone t0=$t0 start=4012 stop=4100 hz=1650 tail=40;
  $mix t0=$t0 hold=$hold start=4100 stop=4443 voices="1650|1850" seed=13 tail=10;
  :put "V.8bis - CRd: 1529 + 2225 Hz, then 1900 Hz";
  $mix t0=$t0 hold=$hold start=5000 stop=5400 voices="1529,2225" seed=14 tail=40;
  $tone t0=$t0 start=5400 stop=5543 hz=1900 tail=0;
  :put "V.8bis - messages at 300 baud";
  $tone t0=$t0 start=5809 stop=5950 hz=980 tail=40;
  $mix t0=$t0 hold=$hold start=5950 stop=6689 voices="980|1180" seed=15 tail=10;
  $tone t0=$t0 start=6724 stop=6860 hz=1650 tail=40;
  $mix t0=$t0 hold=$hold start=6860 stop=7306 voices="1650|1850" seed=16 tail=10;
  $tone t0=$t0 start=7457 stop=7600 hz=980 tail=40;
  $mix t0=$t0 hold=$hold start=7600 stop=7937 voices="980|1180" seed=17 tail=10;

  # 8.2 s - ANSam. The 10ms breaks are its phase reversals, 450ms apart.
  :put "ANSam - 2100 Hz";
  $tone t0=$t0 start=8186 stop=8626 hz=2100 tail=0;
  $tone t0=$t0 start=8636 stop=9076 hz=2100 tail=0;
  $tone t0=$t0 start=9086 stop=9332 hz=2100 tail=40;
  :put "CM - the calling menu, under the answer tone";
  $mix t0=$t0 hold=$hold start=9332 stop=10450 voices="2100,980|1180" seed=18 tail=40;
  :put "JM - both menus at once";
  $mix t0=$t0 hold=$hold start=10450 stop=11640 voices="980|1180,1650|1850" seed=19 tail=40;
  $mix t0=$t0 hold=$hold start=11640 stop=11698 voices="1650|1850" seed=20 tail=10;

  # 11.7 s - phase 2 under an 1800 Hz guard tone.
  :put "Phase 2 - INFO0, tone A 2400, tone B 1200";
  $mix t0=$t0 hold=$hold start=11705 stop=11775 voices="1800,2000~2800" seed=21 tail=40;
  $mix t0=$t0 hold=$hold start=11775 stop=12050 voices="1800,2400,800~1600" seed=22 tail=40;
  $mix t0=$t0 hold=$hold start=12050 stop=12251 voices="1800,800~1600,2000~2800" seed=23 tail=40;
  $mix t0=$t0 hold=$hold start=12251 stop=12454 voices="1800,1200,2400" seed=24 tail=40;
  :put "L1/L2 - probing the line";
  $tone t0=$t0 start=12454 stop=12861 hz=150 tail=40;
  $mix t0=$t0 hold=$hold start=12861 stop=12936 voices="1800,2400,1200" seed=25 tail=40;
  $tone t0=$t0 start=12936 stop=13028 hz=1200 tail=40;
  $tone t0=$t0 start=13028 stop=13480 hz=150 tail=40;
  :put "INFO1 - the results";
  $mix t0=$t0 hold=$hold start=13480 stop=13600 voices="1800,2400,800~1600" seed=26 tail=40;
  $mix t0=$t0 hold=$hold start=13600 stop=13857 voices="1800,2400,800~1600,2000~2800" seed=27 tail=10;

  # 13.9 s - phase 3. A low square for rasp against a high tone for hiss.
  :put "Phase 3 - training";
  $mix t0=$t0 hold=$hold start=13943 stop=14780 voices="150~700,1800~3700" seed=28 tail=40;
  $mix t0=$t0 hold=$hold start=14780 stop=16720 voices="150~600,1500~3300" seed=29 tail=40;
  $mix t0=$t0 hold=$hold start=16720 stop=20950 voices="150~700,1800~3700" seed=30 tail=40;

  # 21.0 s - the DIL, then a 111 Hz buzz and a 1350 Hz blip before phase 4.
  :put "DIL - the 63.5 Hz buzz";
  $buzz t0=$t0 hold=$hold start=20950 stop=22900 hz=63 accent=127 period=79;
  $tone t0=$t0 start=22900 stop=23240 hz=111 tail=40;
  $mix t0=$t0 hold=$hold start=23240 stop=23423 voices="1350,150~600" seed=31 tail=40;

  # 23.4 s - data, until the modem mutes its speaker mid-noise.
  :put "Phase 4 and data";
  $mix t0=$t0 hold=$hold start=23430 stop=26887 voices="150~700,1800~3700" seed=32 tail=10;
  :put "CONNECT - speaker off";
}