What are 3 1/2 digit and 4 1/2 digit displays?

 

3 and half digit & 4 and a half digit displays

 

3 1/2 digit has a maximum count of 1.999

4 1/2 goes to 1.9999.

The MSB is either 0 or 1. Don't know why that is considered a "half" digit.

 

that's not half...half is 0.5..........no

 

Don't know why that is considered a "half" digit.

Undoubtedly because some marketing person thought it up long ago...

 

It can be used to show values from -1999 to 1999, and can include a decimal point, by lighting up the red segments, to suit the number you want.

If you count the number of segment connections to each digit, you'll see that the 1st has only 4 wires, because there are only 4 segments.

The other digits have 8 wires (Although we often refer to these as '7 segment' displays, if you include the decimal point, there are really 8 segments)

We say that the left hand digit is only half a digit, as it has half the number of segment connections of a full digit.

Here is a sample of a 3 1/2 Digit Display:

this was from here >>> http://www.london-electronics.com/digitresolution.php

B. Morse