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Products   >   I/O Expansion Modules   >   Communications Modules   >   Emerald-MM-8EL 4- or 8-Port Serial Module
4 or 8 multiprotocol serial ports
100% software configured -- no jumpers
Maximum baud rate:
    RS-232 mode: 1Mbps
    RS-422/485 mode: 10Mbps
16550 compatible octal UART with
256-byte TX/RX FIFOs
Software configurable for RS-232/422/485 protocols
SP330 multiprotocol transceivers, one per port
Models with or without opto-isolation
Programmable RS-422/485 termination
Independent 2500VRMS isolation port by port
+/-15KV ESD protection on each port
Staggered turn-on of isolated devices for reduced inrush current at power on
8 programmable digital I/O or analog input lines
On-board microcontroller manages and stores configurations
All configuration done via software; no jumpers
Comprehensive software suite enables easy configuration and control
Latching connectors for imcreased ruggedness
PCIex1 host interface using PCIe/104 OneBankTM connector
Supports Linux, Windows XP, 7, Vista & 2000
Extremely rugged -40°C to +85°C operating temperature
MIL-STD-202G shock and vibration compatible
PCI/104-Express form factor
Customers who use this product also use:

This product can be customized and ruggedized. Click here for more information.
See Emerald-MM-8EL 4- or 8-Port Serial Module Technical Resources
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EMM-8EL Datasheet
(.pdf, 241.1 kb)
EMM-8EL User Manual
(.pdf, 625.4 kb)
Emerald-MM-8EL Universal Manual
(.pdf, 722.2 kb)
(.zip, 18.9 kb)
EMM-8EL Linux Drivers
(.zip, 2.9 MB)
EMM-8EL Windows Drivers
(.zip, 128.8 MB)

Emerald-MM-8EL 4- or 8-Port Serial Module

High Performance PCI/104-Express 4- or 8-Port RS-232/422/485 Serial I/O Module with Opto-isolation

Emerald-MM-8EL 4- or 8-Port Serial Module
click for a larger image
Block Diagram
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The Emerald-MM-8EL-XT is a family of high performance PCIe/104 "OneBank" serial I/O modules offering 4 or 8 multiprotocol serial ports with software-controlled configuration and optional opto-isolation.

Available Models

Model # Description
EMM-8EL-XT 8-Port serial module with opto-isolation
EMM-4EL-XT 4-Port serial module with opto-isolation
EMM-8E-XT 8-Port serial module without opto-isolation
EMM-4E-XT 4-Port serial module without opto-isolation

The serial ports are based on a high speed PCIe octal UART with 256-byte TX/RX FIFOs and auto RS-485 transmit control. Each serial port can be independently configured for RS-232, RS-422, or RS-485 protocols, along with programmable 120-ohm line termination. Each port is independently isolated with an isolated power + signal chip, plus additional isolators for control signals. The board features intelligent power management that limits inrush current on power-up and also enables power-down of unused serial ports for power savings.

Opto-isolated models feature independent 2500VRMS isolation circuits for enhanced reliability in vehicle or long cable applications. All ports also feature +/-15KV ESD protection. Each serial port is available on an independent latching connector for increased isolation and ruggedness. With its wide operating temperature range and high resistance to shock and vibration, the EMM-8EL-XT fits a wide variety of rugged and on-vehicle embedded serial I/O application needs.

EMM-8EL-XT also offers 8 digital/analog I/O lines which are programmable from the on-board microcontroller. Each I/O line can be configured for digital input or output. Seven of the I/O lines can be configured for 12-bit A/D input with selectable 0-2.048V or 0-3.3V input ranges.

EMM-8EL-XT contains no configuration jumpers; all configuration and control is done with an onboard microcontroller. All configuration settings are stored in the microcontroller's flash memory and are automatically loaded on power-up.

Software Support

The EMM-8EL-XT family is compatible with Windows 7/Vista/2000/XP and Linux 2.6. All drivers are shipped with the product.

The on-board microcontroller is managed with a comprehensive software suite that makes configuring the EMM-8EL-XT fast and simple. A graphical control panel, a console application, and drivers for Windows and Linux are provided to enable convenient configuration of the board and control of the I/O features in a laboratory or system assembly environment, or embedded in the customer's application software.

GUI Control Panel CLI Control Panel
GUI Control Panel Command Line Interface Control Panel

Block Diagram

Emerald-MM-8EL Block Diagram


Serial Ports
Number of serial ports 4 or 8
Protocols RS-232, RS-422, RS-485 configured with software, no jumpers
Maximum baud rate RS-232 mode: 1Mbps
RS-422/485 mode: 10Mbps
UART 16550 compatible octal UART with 256-byte TX/RX FIFOs
Transceivers SP330 multiprotocol transceivers, one per port
Communications parameters 5, 6, 7, or 8 data bits; Even, odd, or no parity
Termination Software programmable RS-422/485 termination
Isolation Independent 2500VRMS isolation port-by-port
ESD protection +/-15KV on each port
Short circuit protection Continuous, all outputs
RS-232 mode
Input Impedance 3KΩ min
Input voltage swing ±30V maximum
Output voltage swing ±5V min, ±7V typical
RS-422/485 modes
Differential input threshold -0.2V min, +0.2V max
Input impedance 12KΩ minimum
Input current +1.0mA max (Vin = 12V)
-0.8mA max (Vin = -7V)
Differential output voltage 2.0V min (RL=50Ω)
High/low states differential
output voltage symmetry
0.2V max
Digital / Analog I/O
Number of lines 8 individually programmable lines:
8 as digital input or output
7 as 12-bit analog input
Analog input ranges 0-2.048V or 0-3.3V
Host interface PCIex1 using PCIe/104 OneBank connector
Inrush current Staggered turn-on of isolated devices for reduced inrush current at power on
On-board microcontroller On-board PIC microcontroller with flash to manage and store configurations
Connectors Latching connectors on all ports for increased ruggedness
Dimensions 3.55" x 3.775" (90mm x 96mm)
Conforms to PCIe/104 OneBank form factor supporting Type 1 and Type 2
Power supply +5VDC ±5%
Current consumption 160mA typical, all outputs unloaded
Software drivers Windows Embedded Standard 7, XP, 2000 and Vista
Linux 2.6.16, 2.6.31 and 2.6.32
Operating temperature -40°C to +85°C (-40°F to +185°F)
Operating humidity 5% to 95% non-condensing
Shock MIL-STD-202G compatible
Vibration MIL-STD202G compatible
MTBF 579,352 hours at 20°C
Weight 2.5oz (71g)
RoHS Compliant

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Emerald-MM-8EL 4- or 8-Port Serial Module
available models:
8-port PCI/104-Express Serial Module with opto-isolation
4-port PCI/104-Express Serial Module with opto-isolation
8-port PCI/104-Express Serial Module no opto-isolation
4-port PCI/104-Express Serial Module no opto-isolation
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Cables and accessories
available models:
Cable Kit with 4 serial cables & 1 digital/analog cable
Cable Kit with 8 serial cables & 1 digital/analog cable
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