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7-segment characters

A project log for NEDONAND homebrew computer

NEDONAND is 8-bit homebrew computer entirely built out of many 74F00 chips (2-input NAND gates)

SHAOSSHAOS 03/27/2016 at 12:243 Comments

There is a very useful Wikipedia article about this topic:
https://en.wikipedia.org/wiki/Seven-segment_display

Especially the table with 128 7-segment "characters" - I put hexadecimal digits around it to make it easier to see what to send to the register to display (and highlighted everything looks like numbers or letters):

NEDONAND LITE has this table for "characters" with codes from 0x00 to 0x7F - and next 128 characters with codes from 0x80 to 0xFF simply add a dot at the right-bottom corner. Five indicators display content of 5 registers A, B, C, D and E.

Discussions

Garth Wilson wrote 04/06/2016 at 20:15 point

My first home-made computer (shown at http://6502.org/users/garth/projects.php?project=3) had an 8-character 7-segment (plus decimal point) display.  This was 1985.  I seem to remember getting all the letters and some special characters in, but it definitely took some imagination, and you couldn't pick between upper- and lower-case.  For example, the W was an upside-down capital "A", the M was an upside-down capital "U", the n was an upside-down lower-case "u", the h was normal but K had to be "H".

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SHAOS wrote 04/06/2016 at 20:32 point

When I did some Internet search about this topic I liked when people
showed W as 0xA2 and M as 0x51 (codes as per table above), but K is
trickier...

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SHAOS wrote 04/06/2016 at 20:37 point

Some use 0x07 as K and 0x64 as X

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