PCI Express 2-Port RS-232, RS-422, RS-485 Isolated Serial Interface
The 7203e PCI Express serial interface provides two optically isolated serial ports, each individually configurable for RS-232, RS-422, or RS-485. Each serial port utilizes a 16C952 UART with 128-byte Tx/Rx FIFOs that enables data rates to 460.8K bps for reliable high-speed communications in data intensive applications. This high-performance UART includes 9-bit framing support and is register compatible with legacy 16550 software applications. In addition, the board derives a 62.5 MHz clock from the PCI Express link. This ultra-high speed clock is divided by a flexible 8-bit clock prescalar with 1/8 steps to provide support for the widest range of standard and non-standard baud rates.
In RS-485 mode the board provides automatic control of the RS-485 driver in hardware, eliminating the need for application software control. This allows the 7203e to be used with standard serial communications applications and removes the risk of bus contention and data corruption. Additionally, RS-485 network termination, critical to robust multi-drop communication, can be selectively added to the circuit via DIP-switches. In RS-232 mode, all modem control signals are implemented for maximum compatibility with a variety of serial peripherals.
Sealevel’s SeaCOM software makes installation and operation easy using Microsoft Windows and Linux operating systems.
The 7203e is a PCI Express X1 board compatible with any standard size PCI Express slot.
- Each port individually configurable for RS-232, RS-422, or RS-485
- Optical isolation provides protection against transients and ground loops
- 16C952 buffered UARTs with 128-byte FIFOs
- Oscillator and clock prescalar support wide range of baud rates
- Supports 9-bit protocol framing
- Each port supports data rates to 460.8K bps
- RS-485 line termination, pull-up and pull-down resistors for each port are selectable via dipswitch
- RS-485 ECHO can be enabled/disabled via dipswitch
- PCI Express X1 compliant
- Compatible with all standard size PCI Express slots
- All modem control signals implemented in RS-232 mode
- Automatic RS-485 enable/disable in hardware
- Board includes two DB9M connectors