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Unless I am missing something from your schematic, SW1 would need to latch in order for D2 to be illuminated along with D1 (assuming a working program). This would involve reading GP4 (IC Pin #3... incorrectly labelled as GP3.....) firstly as input, de-bouncing and then modifying TRISIO to output, in order to light D2. If SW1 is a momentary push switch, a release will result in an open-circuit to D2 and not a chance of it being lit.
Also, if SW1 is latching, when a reset occurs from SW2, SW1 will still read closed and D1 & D2 will be lit.
Since GP0, GP1 & GP5 are currently unused, why not redo the scematic and use one of them exclusively for SW1 or D2?
SW1 is a open circuit device with LED indication so it can't be separate with LED & will turn off if SW1 opened,its ok.
I do some searching on the net & found maybe D-type Flip Flop 4013 logic device is what I want. But I'm an electronic beginner so won't understand the circuit. Is nice if U guys can point me some.
Even though the LED is incorporated in the switch, there should be separate terminals for the LED in SW1. Check the switch terminals with an Ohm meter and determine the actual switching contacts Vs the LED terminals.
If you can provide a link to the actual switch you have, or take a look at it's datasheet yourself, the job will be made much easier...
For now, imagine the switch has 4 terminals.
You would probably find that only 2 are the ones connected to the switch contacts and the other 2 are connected to the LED. (If 6 terminals, 2 for LED & 4 for switch contacts. etc.)
From here, you could connect SW1's switching contacts to GP4 as you have already, but use a pull-up resistor to stop GP4 from floating when not pressed, then monitor for a ground when pressed. Don't forget a de-bounce routine.
Now, the other 2 terminals could be connected to ground and through a current-limiting resistor to Q1, to control the switch LED.
Or, you could use one of the un-used GP pins to rapidly flash the switch LED, whilst D1 remains constantly lit.
Some food for thought.
Added after 12 minutes:
P.S. Are you really using 24V to supply this circuit, or is that just an "example" schematic?
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