GE
Intelligent Platforms

PMC423

16 Port Serial Controller, Front and Rear I/O
Features

Benefits

•t 16 Port Serial Controller with two 16-bit
Timer/Counters

The PMC423 provides a uniquely effective solution for integrating serial I/O requirements into
a VMEbus or CompactPCI system. Implemented
on a single PMC card, the PMC423 is fully compatible with current generation VMEbus and
CPCI Single Board Computers, as well as any
special purpose processor that includes a PMC
connector. In addition, card edge PCI systems
can be accommodated using GE Intelligent
Platforms’ PMC239 adapter for rapid prototype
and development.

•t PMC/PCI Form Factor (66 MHz Capable)
•t 16 ports routed to the front and rear
•t Read/Write Burst Operation
•t Baud Rate from 150bps - 6.25Mbps
•t Software selectable RS232, RS422 & RS485
(Full Duplex & Half Duplex)
•t All Ports Fully Independent (16C550
Compatible Registers)

Traditional single and multi-port Serial
Interfaces place a high overhead on the
host processor by requiring per-characterattention (i.e. each received and transmitted
character generates interrupts and programmed I/O from the host.) Six features of
the PMC423 remove this overhead:
•t Data transfer in Byte, Word and Doubleword, capable of Read/Write Burst
•t FIFO buffers to avoid data overrun (64
Bytes on each port)
•t Transmit and Receive FIFO Level Counters
•t Automatic Xon/Xoff Software Flow Control
•t Interrupt Source Register for all 16 ports
•t RS485 Half-duplex Control with
Selectable Delay

Each of the sixteen ports has individually programmable line drivers to set any of the most
popular signaling types: RS232, RS422 and
RS485 (full duplex & half duplex with termination or non-termination option). The signaling
characteristics are set by software. Baud rate
of each serial port is separately programmable. Supported rates are from 150bps to 6.25
Mbps. The PMC423 does not route the RTS/
CTS and DTR/DSR signals to the I/O ports.
In addition, the PMC423 has two 16-bit general purpose Timer/Counters.
External Connection
Depending on the application’s requirements,
the PMC423 offers both front and rear I/O.
The front I/O is a high density 68-pin connector. The 68-pin connector mates with a
separate cable to provide standard connection to 16 DB-9 male connectors (purchased
separately). For applications that require rear
I/O, the ports are wired to the J4 connector of
the PMC423. Custom cables can be fabricated
by GE Intelligent Platforms on request.