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internal wiring of the internet chair (should not need to be changed during the exhibit)

                  use      seatwire  default_volt_dec_alpha x86dos x86gnux

computer's +5v    power      red

13 in                                  5 sltc
      25  ground             black
12 in                                  5 pe
      24  ground
11 in                                  5 -busy
      23  ground
10 in             ck(IRQ 7)  yel       5 ack
      22  ground
9 d7           spikes retract when hi.21
      21  ground
8 d6                buzzer when high .21
      20  ground
7 d5                                 .21
      19  ground
6 d4                                 .21
      18  ground
5 d3                                 .21
      17  io                             -slct_in
4 d2                                 .21
      16  io                             init (out)
3 d1                                 .21
      15  in                             error (in)
2 d0                       green     .21
      14  io                             -auto_fd_xt (in)
1 io                                  5

             license (spikes)  white
             safety buzzer     blue

(paraport total: 8d, 4io, 5in; thus could in principle have 12outs, or 13ins)

phone wire (as my old dusting cables) standard order of colors:

easy way to remember the colors:
when the credit carte blanche swipes a license form retracts spikes;
when the time's up, a blue safety shield is heard by way of loud horn or buzz
also, when the seat is licensed (power supplied to retract spikes), the
LED sign could be turned off???

Convention of Prof. Mann: red = +5v
                          yel = clock
                          green = data
                          black = ground
yel goes (sometimes through an inverter (7404)) to pin 10 of parallel port;
green goes to pin 2 of parallel port which is data 0 (D0).
black goes to pin 25 of parallel port (one of the grounds)