sushant_21
Junior Member level 3
(Help)
I am having problem in seven segment, the problem is when a-g segment glow, the dp is not glowing . DP only glow when rest of segments are off.
I have tried almost all that I can do from firmware,
I tried setting output port setting to open drain , disabling internal pull up. But it doesn't seem to work.
This is small code to lit every segment of 7seg every 1s.
Hers the video link for problem,
video
JP2 and JP3 IO lines are directly connected to LPC1768 IO pins.
I tried Removing R30 and placing 10k between Collector and DP.
Also tried changing R28 to 1.2k and removing r29
I have also tried Q11 transistor replacing with BC847, BC858 but its not working..
So finally I ask for your help, i believe it's hardware related , sadly hardware is developed by different party.
The problem is, I have always used 3.3V to drive segments, but here they used 12V , DP or led should work with 2n2222 but it's not couldn't get why
I am having problem in seven segment, the problem is when a-g segment glow, the dp is not glowing . DP only glow when rest of segments are off.
I have tried almost all that I can do from firmware,
I tried setting output port setting to open drain , disabling internal pull up. But it doesn't seem to work.
This is small code to lit every segment of 7seg every 1s.
Hers the video link for problem,
video
JP2 and JP3 IO lines are directly connected to LPC1768 IO pins.
I tried Removing R30 and placing 10k between Collector and DP.
Also tried changing R28 to 1.2k and removing r29
I have also tried Q11 transistor replacing with BC847, BC858 but its not working..
So finally I ask for your help, i believe it's hardware related , sadly hardware is developed by different party.
The problem is, I have always used 3.3V to drive segments, but here they used 12V , DP or led should work with 2n2222 but it's not couldn't get why
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