Student Contributed Documentation

Useful VHDL Code - LED

As many people are going to use LED, we will give out our VHDL code for the LED so that others can use it.

The decoding from binary number to 7 segments are done internally, i.e. all done by VHDL (recommended by the professor). This means that we will have 7-bit output from the Actel chip directly connected to the LEDs and do not need to have any external BCD-7_segment decoder.
We will connect the LED externally to 5V. In this way, when we output a "0" to a particular segment, that segment will be on and vice versa.
Here, we have included 2 entities:
- mdecoder is to decode the binary number into two binary number. For example, input number 23 will be decoded into "2" and "3" separately.
- decoder is to decode the binary number into 7-segments. For example, input number 8 will be decoded into "0000000".
- m_decoder has 43 modules while decoder has 21 modules.