After a factory cleanup, Serial1 is the default serial port for program development and downloading. The Serial1 and Serial2 ports have identical communications capabilities, although more of the Serial1 signals (both RS232 and RS485) are made available on the Docking Panels headers and connectors. Rather, the UART deduces the correct time to sample the incoming signal based on the start and stop bits in the signal itself. The communications is asynchronous because no synchronizing clock signal is transmitted along with the data. They translate the bit-by-bit data on the serial cable into bytes of data that can be interpreted by the operating system or by your application program. The Serial ports are implemented by the dual on-chip hardware UARTs (Universal Asynchronous Receiver/Transmitters) on the Freescale 9S12 (HCS12) microcontroller.Įach UART (sometimes referred to as a 'USART') controls the serial-to-parallel and parallel-to-serial conversion and performs all of the timing functions necessary for one asynchronous serial communications link. The default baud rate after a factory cleanup is 115200 baud. Each serial port can be configured for the RS232 or RS485 protocol, and runs at standard baud rates up to 115,200 bits per second. The PDQ Single Board Computer ( SBC) has two asynchronous serial communications ports named Serial1 and Serial2. Can be used to communicate with other peripheral devices if multi-processing is not required. Used for inter-processor ( IP) communications on multi-processor systems such as the PDQScreen. Each device must have unique hardware chip select signal. Each device must have unique numeric address.ģ-wire multi-drop bus, up to 10 MBaud if SPI bus master, up to 5 MBaud if SPI slave. The RS485 signals are not available on the Docking Panel.Ģ-wire multi-drop bus, up to 100 Kbaud. All signals are also available on the Docking Panel.

Rs485 bus