why when I simulate this circuit - two LEDs connected to 555 output, the LED to ground shows current flow but the LED connected to Vcc to pin 3 output shows no current.
why doesn't it show current when the 555 output goes low?
maybe a reference to ground?? issue.
I think the simulation program is stupid.
When the output of the 555 goes low then the upper LED should light.
When the output of the 555 goes high then the lower LED should light.
The simulation also shows an output voltage that is too high when the output of the 555 is high.
but regardless the led connected to Vcc to pin 3 should show a high when the 555 output goes low.
the led connected to pin 3 to led to ground shows a high when the 555 goes high.
I will enlarge and straighen out but regardless the led connected to Vcc to pin 3 should show a high when the 555 output goes low.The led connected to pin 3 to led to ground shows a high when the 555 goes high.
It points out the value of careful drawing. Not only does a bad drawing make it difficult to spot your own errors, but most people don't even try to read bad diagrams so getting help is difficult.
but regardless the led connected to Vcc to pin 3 should