On the Subject of Morsematics

Get it? Because it uses morse and maths! I'll see myself out...

  • Every letter of the alphabet is considered to have numeric value equal to its position (A=1, B=2 ... Z=26)
  • Numeric values outside the 1-26 range wrap around (Z+1=A, 26+1=1)
  • Three unique letters are being received on a loop, shown by the three flashing lights in the middle of the module
  • To solve the module, a correct response letter must be sent in morse using the transmit button in the bottom-right
  • The small switch at the top can be used to toggle the received letter lights
Transmitted morse is interpreted based on gaps between button holds.
Holding for more than double the length of the average gap is considered to be a dash, and anything shorter is considered a dot.
When transmitting, E and T are considered equal, as they are indistinguishable.

Take the 4th and 5th character of the serial number, this is your character pair.

Perform each step below in sequence, modifying your character pair progressively:
  • For each indicator that has a matching letter in the received letters; add 1 to the first character of your pair if the indicator is on, or the second character if it is off
  • If the sum of your character pair is a square number, add 4 to the first character; otherwise, subtract 4 from the second character
  • Add the largest received letter to the first character in your pair
  • If any received letters are prime, subtract them from the first character in your pair
  • If any received letters are square, subtract them from the second character in your pair
  • If batteries are present and any received letters are divisible by the number of batteries present, subtract those received letters from both characters in your pair
After performing all steps, perform whatever rule applies below:
  • Characters are equal: Transmit the first character
  • First character larger: Transmit the difference of the two characters
  • Second character larger: Transmit the sum of the two characters
A1 N14
B2 O15
C3 P16
D4 Q17
E5 R18
F6 S19
G7 T20
H8 U21
I9 V22
J10W23
K11X24
L12Y25
M13Z26