Max7219 always on

george miyagi

i've been trying to get the MAX7219 to work on a LED matrix.

using the following code:
Clock CON 2
DPin CON 0
Load CON 1
LOW Load
SHIFTOUT DPin, Clock, MSBFIRST,[noparse][[/noparse]$090F\16]
HIGH Load
row VAR BYTE
col VAR BYTE
row=%10000000
Main:
row = row >>1
IF row = 0 THEN row = %1000000
FOR col = 1 TO 5
SHIFTOUT Dpin,Clock,MSBFIRST,[noparse][[/noparse]col, row]
PULSOUT Load,30000
PAUSE 50
NEXT

GOTO Main

problem is, the lights always stay on. i can see flickering (extra brightness) representing where they should be on.
but can't get them to switch off.
help please!!


(i just recently edited the code to intialize - the naimation plays superbright onto of all lights being on medium bright)

Post Edited (george miyagi) : 6/17/2005 9:46:23 AM GMT

Chuck Rice

It looks like the problem might be in the PAUSE 50. I think that would be a really short time period. Something like 1/20 th of a second. What happens if you change it to PAUSE 5000 (5 seconds). That would give you time to see it before the next character went out. -Chuck-

slotcarz

Maybe this might help. I had a similar problem and I had to reverse the connections on the LED's. I had my cathodes on the rows and the (-) on the columns. After I switched the connections the Max7219 worked properly. I just was only able to use sample code to make it work, which it did. Maybe this will work for you or maybe not... good luck

george miyagi

mmmm. sorry. none of these worked