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.g., RS part number 278-1221)(1) Pair wire strippersIn addition to these components, you will need access to a soldering iron and some solder to assemble the connector.You will also need a 6ft DB26 male to male cable, although the computer laboratory will probably supply this cable.To assemble the connector for your kit, you will need to create fifteen strips of wire approximately one foot long.Strip about 1/8th inch insulation from one end of the wire and about 1/4 inch insulation from the other.Eight of the wiresshould be one color, five of the wires should be a second color, and you should try to use red and black for the remain-ing two wires.If you have only three colors available, use the same color (perferably black) for the last two wires.You should solder the first eight wires (all the same color) to pins two through nine on the DB25F connector.If youlook at the back of the connector, containing the solder lugs, the pins have the following numbers:Pin 1Pin 13Pin 25Pin 14When soldering a wire to the DB25F connector, you must exercise considerable care.You want to apply sufficientsolder to provide a good connection, but you do not want to apply so much solder that you form a solder bridge with anadjacent pin on the connector.Furthermore, you should not strip any excess insulation from the end of the wire that yousolder to the DB25F connector.Ideally, the insulation should be flush against the solder lug on the DB25F after you sol-der the wire.Under no circumstances should you be able to bend the wire and have bare wire make contact withanother wire or pin on the connector.Page Lab 1-9 Lab FwdWhen soldering a wire to a solder lug on the DB25F connector, tryto make sure the insulation on the wire is flush with the solder lug.The wire connected to pin 2 is data line zero or D0, the wire connected to pin 3 is D1, the wire connected to pin 4 isD2, etc.These eight wires are the data outputs from the PC s parallel printer port.Pin 1D0 D1 D2 D3 D4 D5 D6 D7Data Output Lines on the DB25F connector (Back View)The next five wires (preferably all the same color, and a different color from the eight wires above) handle inputfunctions on the parallel port.You should solder these five wires onto pins 10, 11, 12, 13, and 15 on the DB25F connec-tor.We will call these signals I5, I4, I3, I2, I1, and I0, respectively.Note that these inputs are not arranged in a logicalorder like the data output lines.Keep this in mind when labelling and using these signals.Page Lab 1-10 Data RepresentationPin 1I3 I4 I2 I 1I0Pin 14Data Input Lines on the DB25F connector (Back View)The remaining two wires provide power and ground for the circuit.If you are using two colors (preferably red andblack), solder the first (red) wire to pin one of the DB25F connector and the other wire (black) to pin 25 of the DB25Fconnector.Pin 1 (Power)Pin 25 (Ground)Power and Ground Lines on the DB25F connector (Back View)Note: If you do not have any soldering experience, you may want to get some help from someone who has sol-dered components together.Although soldering components together is not a difficult task to master, you can damageyour components or even your computer system if your soldering job is really bad.Certainly have your lab instructorcheck over your job before you plug the connector into a computer.Warning: Under no circumstances should you plug your DB25F (female) connector into the DB25M (male) con-nector that appears on the back panel of many different computer systems.The DB25M connector on the back of thecomputer is the serial port.You can damage your serial port hardware if you wire up a circuit described in this lab man-ual and connect it up to the serial port.You might also damage some of the components in your kit.To connect your cir-cuits to the computer, use a 6 ft DB25M to DB25M cable.Plug one end of the cable into the DB25F connector on the backof the computer system (this is the parallel port), plug the other end of the cable into your DB25F connector.Page Lab 1-11 Lab FwdPage Lab 1-12
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