Q. How many Serial Connections can I have with Fitlet2?
Fitlet2 can support up to 3 Serial Connection including the following:
-1x SoC UART RS232 on SBC - Mini Serial Port Connector.
-1x Serial Port RS232/485 Full/Half Duplex configurable with FSCG-Kit - RJ45 Connector.
Q. How can I configure the Serial I want? (RS232/RS485 Full/ Half duplex)
The mini Serial Connector accessible from the SBC has only RS232 capabilities.
For specific configuration, you can use the FSCG-Kit:
Configure the 2 switch on the FACET SBC:
| SW2 | SW1 | |
| ON | RS232 | Full Duplex |
| OFF | RS485 | Half Duplex |
Q. What is the Connection of the Ultra Mini Serial Connector?
Using the Accessory cables:
- CABDB9UMP (DB9-Female)
- ACCENC-ADPUMSER (DB9-Male)
DB9-M | Ultra Mini serial | RS232 Signal |
3 | 1 | TX |
7 | 2 | RTS |
2 | 3 | RX |
8 | 4 | CTS |
4 | 5 | Not Connected |
6 | 6 | Not Connected |
x | 7 | Not Connected |
5 | 8 | GND |
For use of the Ultra Mini Serial Connector Serial Port, you need to verify the following in the BIOS:
Advanced -> PCI Subsystem Settings menu and set the Above 4G Decoding setting to Disabled.
Q. What is the connection for the RS232 and RS485 with the FSCG-Kit FACET?
The connector on the FACET is one RJ45 Port.
Connector is RJ45. No Cable is provided with the FACET.
RJ45 Female Receptacle PINOUT:
| RJ45 | RS232 | RS485H | RS485F |
| Pin | Signal | Signal | Signal |
| 1 | RTS | TXN/RXN | TXN |
| 2 | DTR | ||
| 3 | TXD | TXP/RXP | TXP |
| 4 | GND | GND | GND |
| 5 | GND | GND | GND |
| 6 | RXD | RXP | |
| 7 | DSR | ||
| 8 | CTS | RXN |
RJ45 Male Plug and DB-9 PINOUT:
| RJ45 | RS232 | RS485H | RS485F |
| Pin | Signal | Signal | Signal |
| 1 | CTS | TXN/RXN | RXN |
| 2 | DTR | ||
| 3 | RXD | TXP/RXP | RXP |
| 4 | GND | GND | GND |
| 5 | GND | GND | GND |
| 6 | TXD | TXP | |
| 7 | DSR | ||
| 8 | RTS | TXN |
Q. [Windows] Which COM Port from the Device Manager should I use?
The 2 UartSub Device are the 2 com Ports from the CPU. One of them only can be used as the other is reserved and not accessible from the sides of the SBC.
The 2 USB Serial Port are provided thanks to the FACET. THey have 2 different functions:
- 1 is used for the CAN BUS - NOT AVAILABLE
- 1 is used for the RS232/485 connection.
You can recognise which one is the correct one thanks to the properties:
Q. [Linux] Which COM Port from the Devices should I use?
If you search for Serial Ports: #: dmesg | grep tty
you will get