The Fastcom Universal PCI Bus, Asynchronous RS422/485 adapter utilizes the latest technology to live up to today’s requirements for high bandwidth requirements in communication systems. The Fastcom: 422/2-PCI-335 is capable of operating at virtually any baud rate up to an astounding maximum serial data rate of 6.25 Mbit/s. There isn’t any fine print or asterisk pointing to notes; this card is capable of running at the maximum data rate, without any jumpers or hardware changes, right out of the box.
Designed to comply with the latest PCI specifications, the Universal PCI adapter will operate in both 5V and 3.3V PCI slots. This means the card will work in the high speed PCI-X slots commonly found in most servers as well as the standard PCI slots in desktop PCs. The same PCI adapter can be made to fit into a 2U rack mount server’s PCI slot, without the need for troublesome riser adapters by simply switching the bracket¹, thereby changing the model name to Fastcom: 422/2-LPCI-335. This flexibility allows for a single serial interface board to be used across a wide range of different types of computers, including both current and future computing systems.
The Fastcom: 422/2-PCI-335 adapter utilizes an advanced dual Universal Asynchronous Receiver and Transmitter (UART). Each channel of the 17D152 UART is independently controlled and has its own 16C550 compatible register set. Each UART contains its own receive and transmit FIFO’s of 64 bytes, each with programmable trigger levels.
Both of the UART channels on the board can be independently configured as either RS-422 or RS-485 for full or half-duplex communication. This is implemented using an automatic RS-485 transmitter enable/disable function that permits the hardware itself to regulate data flow by only driving lines while actively transmitting. This provides increased speed and convenience over the older software controlled method, while still allowing the use of the software method of flow control. Optionally, in automatic RS-485 mode, the receiver can be disabled during transmits to avoid a receive echo, common in 2-wire 485 networks.
Additionally, each board utilizes a programmable clock generator to create the UART’s input frequency. The clock generator is capable of generating frequencies between 6 and 50 MHz. Utilizing this feature, it is possible to configure the board to operate at virtually any non-standard serial data rate that the user desires (up to 6.25 Mbit/s maximum).
With the supplied software driver, the ports on the Fastcom: 422/2-PCI-335 will be seen as standard COM ports and can utilize all the same functions as a standard serial device. With the addition of a few simple I/O commands to control the unique features of the board, the standard software interface to a serial port can be used to simplify program design. Example C programs are provided to demonstrate how to effectively use serial interface as well as control the board specific features.
Overall, the Fastcom: 422/2-PCI-335 Universal PCI Bus RS-422/485 adapter is the ideal board for commercial and industrial applications demanding high data rates, reliability and ease of use.
Our software drivers allow the board to be “just another com port” in the system. Programming is done using the standard WIN32 COMM API. The FASTCOM: 422/2-PCI-335 is a switchless design that relies on the plug-and-play functionality capability defined in the PCI 2.3 bus specification to determine address ranges and IRQ settings.