User manual

Connect Tech Xtreme/SBC PCI-104 Single Board Computer - User Manual
Revision 0.03
17
LPC Super I/O
The Xtreme/SBC PCI-104 implements many low speed legacy I/O features with the SMSC SCH3114
Super I/O, which is connected to the Qseven module via the LPC (Low Pin Count) bus. This Super I/O
device provides 4 serial ports, 2 PS/2, and many other status / control features.
Note: the Qseven specification states that all Qseven modules BIOS implementations must support either
the Winbond W83627 or SMSC SCH3114.
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