About the pin layout of a serial connection via COM:

The easiest way to connect several syncMaker PRO is using the COM-Interface that every PC have installed. Set COM-Option on each running syncMaker. Use a NULL-Modem Cable that you can buy in computer shops. Or build the cable by yourself:

9 Pin Female connection:

Master             Slave 
5 GND    ----     5 GND
3 TXD     ----      2 RXD
2 RXD    ----      3 TXD

If you want to use more than one Slave build up a Slave row using e.g. COM1 for Input and COM2 as a thru port. In that case the Thru LED (Slaves) should blink on receiving data. 

If you only have one COM Port available on your systems you have to build up T-Cables. No warranty if this will work with your system! Better you use LAN-Connection instead.

If you use Notebooks give the Infrared Port a chance! This means cool wireless synchronization!