Connect Tech PCIE/104 - Manual (Page 17)

Connect Tech Xtreme/SBC PCIe/104 Single Board Computer and PCIe/104 Qseven Carrier Board - User Manual
Revision 0.02 17
Serial
Description
Two RS232 serial ports are provided on P9 and two RS485 serial ports are provided on P11.
For the RS485 ports, the default configuration is full duplex without any bias or termination. Various
resistors configurations can be populated to enabled TX and RX termination as well as RTS control. The
following diagram shows the available configuration options. Contact Connect Tech’s support department
for further information.
Resistor Function Default
R99 Always enable driver Populated
R101 Always enable receiver Populated
R156 RTS controlled receiver
R160 RTS controlled driver
R98 Receiver termination
R102 Driver termination
R100 Receiver bias
R97 Receiver bias