Max7221

Archiver

Does anyone have code that works with the MAX7221 (8-digit LED
display driver) chip? I have tried the app kits code without success.
I'm only using two large LED (0.800"). Do I need some additional
circuitry because only 2 of the 8 digits are used?

This is the code I've been using (it should configure the chip and
display the number six):

<

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>
DIN con 4
CS con 5
CLK con 9

Loop var byte
maxout var byte
pulse var bit

DIRS=%1111111111111111

pause 1000

shiftout DIN,CLK,1,[noparse][[/noparse]$0901\16]
pulsout CS, 3

shiftout DIN,CLK,1,[noparse][[/noparse]$0A0F\16]
pulsout CS, 3

shiftout DIN,CLK,1,[noparse][[/noparse]$0B00\16]
pulsout CS, 3

shiftout DIN,CLK,1,[noparse][[/noparse]$0C01\16]
pulsout CS, 3

shiftout DIN,CLK,1,[noparse][[/noparse]$0106\16]
pulsout CS, 3

end
<

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>

Thanks!!
--Jeff

Archiver

Your code looks good. Are you sure that all the connections are correct
on the 7221? i.e., cathode on pin 11, segments on the correct pins,
ground to both pins 4 and 9, +5 on 19 and +5 through a resister on 18 to
set the voltage, et al.

-
Ian Bobbitt

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When an error occures:
A novice user blames himself,
a normal user blames the computer,
a power user sighs and gets another cup of coffee.

KB9VEX

ICQ: 14106680

It said requires windows 95 or better, so I installed Linux.