Seven Segments of Pi comes with a 26 way Ribbon Cable
to plug into the 26 pin GPIO Connector of the original Raspberry Pi Models A & B
The more recent Raspberry Pi Models A+, B+ and Model 2 have a
40 pin GPIO Connector so require an adapter

The simplest option is to fit a 26 way GPIO Adapter
as shown on Page 7 of The PiTrol Instructions Manual at
These adapters are widely available
A second option is to use PiDapter40

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