Matrix EB008 Manual Download Page 4

Copyright © Matrix Technology Solutions Ltd.

4

General information

This board provides a quad seven-segment common 

anode display, with an option to operate off only one 

port using links.  This display requires two E-blocks 

ports to operate all four displays.  If only one seven 

segment display is needed then only one E-block port is 

required and a jumper link of the board can be used to 

permanently engage one of the display digits.

1.  Features

•  E-blocks compatible

•  Quad common anode displays

Circuit description

The EB008 quad 7-segment display board circuit can be 

observed on page 6.

To use the full quad 7-segment displays the board must 

be connected to two I/O ports of an upstream board via 

connectors J1 and J2.  Also note that the link (on J4) MUST 

NOT be connected.  As there are not enough pins on the 

connectors, each of the 4 7-segment displays are turned 

on in sequence using connector J2 and the appropriate 

data on connector J1 is displayed.  Connector J2 [Pins 

1 (left display) - 4 (right display)] are used to select 

which of the four 7-seg display digits are active.  The 

signals from J2 are buffered by NPN transistors which 

provide power for the anodes of each digit.  The bits on 

connector J1 [Pins 1-8] connect to the cathodes of each 

segment and hence dictate which segments are lit.  Note 

that each cathode must go low for the segment to light.  

For a program showing 4 digit numbers a multiplexing 

algorithm is required.

The device can still operate using only one I/O port 

connected to J1, but this only allows one (the far left) 

display to be operational.  Placing a link on J4 will 

permanently power the anode of the left hand digit so 

that only cathode data is needed for the individual LEDs 

to illuminate.  Again J1 dictates which segments are 

illuminated.

The board is usually operated off a +5V supply.  This can 

easily be achieved by connecting a +5V supply via a wire 

into the screw terminals.

The diagram below shows which pins illuminate which 

corresponding segment in an individual digital display.  

Please note that in the E-block acrhitecture than pin 1 

will represent bit 0 of which ever port it is connected to.

1.  3.3V operation

This board is compatible with 3.3V systems.

•  Operational link allows operation from only one I/O 

port (two I/O ports required for full quad operation)

•  Compatible with most I/O ports in the E-block range

•  Ease to develop programming code using Flowcode 

icons

•  3.3 voltage compatible

2.  Block schematic

Not supplied.

a [Pin 1]

g [Pin 7]

d [Pin 4]

f [P

in 6]

e [P

in 5]

b [P
in 2]

c [P
in 3]

dp [Pin 8]

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