1 Oct
2006
1 Oct
'06
5:09 p.m.
Ethan Dicks wrote:
I'm prototyping an LED display thingie and was
trying to find a
representation of how folks used to do letters on a 7-segment display.
The two historical examples I came up with were the KIM-1 and a Byte
magazine article between about 1977 and 1981.
what I need is the definitive source for the patterns.
For the KIM-1, the only definitive source is the ROM,
and that only has patterns for hexadecimal:
* HEX-TO-LED SEGMENT CONVERSION TABLE
* SAME AS $1FE7 IN THE KIM ROM.
DB $BF,$86,$DB,$CF ;0 1 2 3
DB $E6,$ED,$FD,$87 ;4 5 6 7
DB $FF,$EF,$F7,$FC ;8 9 A b
DB $B9,$DE,$F9,$F1 ;C d E F
As Mr. Veit has written, the First Book of KIM has
more letters. Another source is issue 1 of the
KIM-6502 User Notes, which has a slightly different
alphabet:
DB $BD,$F6,$86,$9E ;G H I J
DB $B8,$BF,$F3,$ED ;L O P S
DB $BE,$EE,$FC,$D8 ;U Y b c
DB $DE,$F1,$EF,$F4 ;d f g h
DB $84,$9E,$86,$D4 ;i j l n
DB $DC,$F3,$D0,$F8 ;o p r t
DB $9C,$EE,$C0 ;u y minus
DB $F0,$B7,$D4,$E7 ;k m n q
DB $BE,$EA,$9C,$94 ;q v w x
DB $C9,$D3,$80 ;z ? space
You can find the KIM-6502 User Notes at
www.6502.org in the publications section.
--
Paul R. Santa-Maria
Temperance, Michigan USA