I need a logic inverter that lights up an LED when the stepper driver is enabled (the EN pin is reversed). I created the following diagram:
I fear that The placement of the EN pin in the circuit will hinder the transistor? Could someone tell me if this is correct or not? And if not, how would I fix it?
Thanks in advance.
Add a second base resistor, feed the EN signal to this resistor.
The way it is drawn, the LED will go out when the transistor is on.
Tell us more about the EN signal.
What is the purpose of the switch?
Can you draw a truth table for the operation? I feel you are looking for a logic gate (this OR that ) rather than an inverter
The EN pin is the Enable input pin of the stepper driver A4988.
Truth table that I wish to achieve is as follows;
Closed | HIGH | LOW
Open | LOW | HIGH
EN Pin is active low input, when pulled LOW(logic 0) the A4988 driver is enabled. By default this pin is pulled low so the driver is always enabled, unless you pull it HIGH.
Should work fine, the En pin being pulled low would not interfere with the transistor or LED. The switch would pull it high, turn on the transistor and turn off the LED.
Dont forget to change the topic title & add "SOLVED".
Since you already have an arduino, why not just connect a wire from the enable pin to a digital input and
read it with digitalRead() ? (and then turn on a led connected to a digital output )
In your other thread, you mentioned spare inverter gates. Did you run out of those?
In your other thread, you mentioned spare inverter gates. Did you run out of those?
It's a tossup which approach involves more work....
aarg:
In your other thread, you mentioned spare inverter gates. Did you run out of those?
So this is an inappropriate "cross" posting then - and should be ignored in favour of the original? 
So this is an inappropriate "cross" posting then - and should be ignored in favour of the original?
Please submit links to all your illegal cross posts...
Mine?
"Mine ?"
No, of course not yours.
The OP's. ( or is it "The OPs' " ?