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Diamond Point International

Diamond Systems Mercator II - PC/104-Plus Quad 10/100 Ethernet + DIO

2 PCI-Based 10/100 Ethernet Controllers, 24 ISA-Based Digital I/O Lines


The Mercator II PC/104-Plus module integrates 2 PCI-based 10/100 Ethernet ports with 24 user-configurable digital I/O lines in the compact and rugged PC/104 format. This 2-in-1 combination of Ethernet and digital I/O can help lower the size and cost of your embedded system by eliminating one additional board from your PC/104 stack.

The Ethernet ports are driven by two dual Micrel KSZ8842 Mac + Phy PCI controller chips, two ports per chip, and are NE2000 compatible. Each chip has a unique MAC address; therefore, only two Ethernet ports are visible to the end user for active communication. The other two ports work in switch fashion to enable daisy chaining of networks with one port on the chip as an uplink to a network while the other port provides active communication on the network.

The 24 digital I/O lines are based on an 82C55 chip and feature programmable direction in 4- and 8-bit groups. All I/O lines contain user-configurable 10K ohm pull-up resistors for convenience.

Extended temperature capability (-40ºC to +85ºC) enables the board to operate in environments with extreme temperature swings, such as vehicles or outdoor installations. In addition, the board may be custom-configured with 0-ohm resistors in place of jumper blocks for increased ruggedness in high-vibration environments.

Diamond Systems offers appropriate mating cables for your convenience. Cable number C-PRZ-02 provides a panel-mountable RJ-45 connector for the Ethernet, and cable number C-26-18 is a 26-conductor ribbon cable for the digital I/O.

Configuration Options

Several features are configurable using either a dual-row 2mm size jumper block or a switch. Provision is made on the board for zero-ohm resistors to replace jumpers to enable a hard-wired configuration.

  • Digital I/O base address (8 address options with 3 jumpers)
  • Digital I/O configuration: pull-up enabled or disabled
  • PCI slot selection for each Ethernet port



FunctionIEEE 802.3 10Base-T and 100Base-TX compatible
Interface(s)4 10/100 Ethernet ports
Controller(s)Dual Micrel KSZ8842 Mac + Phy PCI controller chips
Each chip has a unique MAC address; therefore, only two Ethernet ports are visible to the end user for active communication
Each chip consumes a PCI slot ID
Connection(s)Ethernet ports: 6-pin straight male headers
Mating cable: Ethernet ports: Cable number C-PRZ-02

Digital I/O/Counter/Timers

I/Os24 digital I/O lines

Direction (programmable):
• Ports A and B individually programmable for all input or all output.
• Port C programmable in 4-bit groups for input or output
InputsInput voltage: Low: -0.5V min, 0.8V max, high: 2.0V min, 5.5V max
OutputsOutput voltage: Low 0.0V min, 0.4V max, high 3.0V min, Vcc - 0.4V max
Output current: 2.5mA max, each line
Connectors(s)Digital I/O: 26-pin (2x13) .025" square pin header on .1" centers
Mating cables: Digital I/O: Cable number C-26-18
OtherPull-up resistors: 10KOhm pull-up


ExpansionStandard 16 bit PC/104 interface, 8-bit and 16-bit bus stack through headers are installed
Standard 32 bit PC/104-Plus interface (stackthough)
PCI bus VIO: Can be 3.3V or 5V
Note: Digital I/O is connected to the PC/104 bus, Ethernet ports are connected to PC/104-Plus bus
Electrical+5VDC 10%
MechanicalPC/104 3.55" x 3.775" (90mm x 96mm)
Conformal CoatingOn request
SoftwareSupport for Windows Embedded Standard 7, Windows 7 and Linux 2.6
TemperatureTemperature range (operation): -40°C to +85ºC (-40°F to +185°F)
Temperature range (storage): -40°C to +85°C (-40°F to +185°F)
Humidity5% to 95% noncondensing
Weight3.2oz (90.7g)
Warranty1 Year

Ordering Details

Mercator II PC/104-Plus Quad 10/100Mbps Ethernet Module with 24 Digital I/O, extended temperature
Ethernet cable, 6-pin to RJ-45

Dual 26-pin connectors, 18 inches