M4KSerial4 Excalibur Systems RS-232/422/485 Interface Module

The Excalibur Systems M4KSerial RS-232/422/485 Series Interface Modules are a serial interface module for the multiprotocol Excalibur 4000 family of carrier boards. This module supports up to four independent channels of serial communications, each of which can be selected as RS-485, RS-422 or RS-232. The module operates independently of the host computer, reducing the need for host intervention. The M4KSerial module is based on the Exar XR16L651 Universal Asynchronous Receiver/Transmitter (UART). The device is compatible to industry standard 16C450, 16C550, ST16C580 and ST16C650A UARTs. Each of the M4KSerial's four channels contains a transmit FIFO capable of holding up to 8000 bytes and a receive FIFO capable of holding either 16000 input bytes or 3200 bytes with a 32-bit Time Tag associated with each byte. These large buffers allow application code to transfer large quantities of data with a single non-blocking subroutine call. The 32-bit Time Tag on receive channels is very useful for synchronizing serial data with data from other modules on the 4000 board or on other interface boards. Each channel has a programmable baud rate of up to 2 Mbps and can be configured as RS-232, RS-422 or RS-485.