I cant tell you the pin outs on your marker but I can give you a diagram of the 232 convertor. You will need adobe to view it. Here is a link to the diagram of the convertor at least.Click me for the diagram
If you want you can use a LM1489 in place of the Max232 chip. the 1489 does not need an charge caps and therefore only needs a total of 8wires. 4 inputs and four outputs. Makes for a little cleaner apperance. If you want some info on the 1489 check out www.freetradezone.com
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