Question on how this hardware works/is set up..
I want to use this PRE-MADE 4 x switch, SD Key PCB:
Image of the bottom of PCB so you can see resistor values and traces:
I want to use this in conjunction with a DFPlayer mini, in standalone mode (ie: not used along side an Arduino, like I normally use these)
Here is the 'chart' for the DFPlayer for reference..
** right click >> view image to see true (larger) size.. not sure why it does this?
My question is how these values are calculated and used with this PCB?
Regardless if I decide to use ADKey1 or ADKey2..... (which really just dictates the audio file names)...
I see that each clip is triggered based on the resistance/value of the switch that was pressed.
0K (no resistor/resistance) = triggers clip 0 (or 1, not sure yet)...
3K = triggers clip 2
6.2K = triggers clip 3
I would imagine I'll need to replace the resistors on this PCB, to match that threshold value... but I'm not clear on how this is calculated??
When I look at the bottom of the board and see the resistor values.. they all look to be the same?
So are they added up?
IE: button 1 has no resistor or 0K resistor.. button 2 has a 3k resistor on it..
button 3 then.... needs another addition 3.2k to make it equal >= the 6.2k threshold it is looking for to trigger clip #3?
Or do I just use the stated value on each 'button/switch'? as stated in the diagram/schematic?
ie: button 3 gets a 6.2k resistor, as it only takes that single value into the equation?
So Im not clear is the resistance accumulative? or stand alone?