Technical Manual “Cool FrontRunner” Version 2.7 17.06.2008 Page 15 of 43
An adapter cable with two standard USB connectors is available.
Note:The system BIOS and the USB controller do not support all USB2.0 mass storage devices on the market, which might result in problems when using these. Typical problems are hanging in boot process if a
USB2.0 mass storage device is connected, or slow data transfer rates for USB2.0 mass storage devices. We recommend using USB1.1 mass storage devices instead, if such a problem occurs.
2.14 Serial Ports
Two of the serial ports are located on two IDC headers “COM1” and “COM2”. Adapter cables with standard DB9 male connectors are available. They can either work in RS232 or RS485 mode, selectable in the BIOS. When entering Special Features, COM Port 1 Mode and COM Port 2
Mode can be selected. The third serial Port is located at the supervisory connector and is RS485 only. Termination resistors for RS485 Mode can be set with Jumper X9 as described in chapter
4.18.
COM Port 3 is RS485 only and can be used in 2-wire and in 4-wire systems. In 2-wire systems only
Half Duplex is possible in 4-wire systems both, Half- and Full-Duplex. In 2-wire systems or 4-wire systems with more than 1 transmitters the transmitter must be disabled in receive mode, and enabled in transmit mode. Therefore, program GP34 of the Winbond SuperIO (Logical Device 9, Bit
4). ‘0’ Æ disable transmitter, ‘1’ Æ enable transmitter.
Example in debug mode:
Set the SuperIO into configuration mode by writing 87h to index register 4Eh:
-
-
4E 87
4E 87
Enable Logical Device 9 for programming by writing 09h to register 07h of the SuperIO:
-
-
4E 07
4F 09
Writing to configuration register F1h, Bit 4 sets the GPIO’s value. Be sure not to change the values of the other Bits.
-
4E F1
-
- i 4F
4F xx
Æ Now change only Bit 4!
To enable the transmitters of COM1 and COM2 in RS485 mode set the RTS# signal to ‘1’.
Depending on your operating system driver’s logic, this may mean setting a (non-inverted) RTS bit to ‘0’ in your application software.
The serial ports are programmable in BIOS setup by pressing DEL at boot time. When entering
Integrated Peripherals and then choosing COM Port 1, COM Port 2 or COM Port 3, configuration of the serial ports is accessible.
The following settings are possible for COM1 and COM2:
-
Auto
