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Diamond Systems EMERALD-MM-8E/EL : EMM-4EL-XT

Ruggedized PCI/104-Express 4-Port Serial Module with Opto-isolation

Things Embedded are an official Diamond Systems USA distributor and can supply the EMERALD-MM-8E/EL.


Serial I/O


Diamond Systems


The Emerald-MM-8EL-XT from Diamond Systems 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. An accessory microcontroller manages all port configuration and provides 8 auxiliary digital / analog I/O lines for general purpose use.

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-4EL-XT fits a wide variety of rugged and on-vehicle embedded serial I/O application needs.

Diamond Systems’ EMM-4EL-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.

The EMM-4EL-XT from Diamond Systems contains no configuration jumpers; all configuration and control is done with an onboard microcontroller using application software included with the product. All configuration settings are stored in the microcontroller’s flash memory and are automatically loaded on power-up.

Cable Kits

Cable kits are available for both 4-port and 8-port boards They include individual cables with dB9 male connectors for each serial port and a ribbon cable for the auxiliary analog/digital I/O.


Brand & Model Diamond Systems EMERALD-MM-8E/EL : EMM-4EL-XT
Ruggedized PCI/104-Express 4-Port Serial Module with Opto-isolation
Features Compact
Serial Ports
Number of serial ports 4
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 0.2V max
output voltage symmetry
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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