Syscall 2: Firmware, home

SignalChapter 1: Arrival

2RELAY

The task

Use OUT on core a and IN on core b to pass each value along the wire between them.

Every value from X must reach P through both cores.

The board

The board of RELAY2 cores: a and b. Inputs X; outputs P.aSC-2 15 LINESbSC-2 15 LINESP0P1P0P1XP
The board as the puzzle screen lays it out. Cyan pins read, lemon pins write, violet pins go both ways. On a narrow screen, scroll the board sideways to see all of it.

Key idea

Values travel from core to core along wires.

Hints

Each hint goes a step further than the one before. Open them one at a time.

Hint 1Show

Each core has its own pins. a.P1 and b.P0 are the two ends of one wire.

Hint 2Show

Core a reads X on P0 and writes to b on P1, as in FIRST SIGNAL.

Hint 3Show

Core b needs a program too: IN P0 takes what a sent, and OUT P1 writes it to P.

Solution

Reveal the Full SolutionThe complete program for RELAY. Open it only when you want the answer.

The reference program

The game's own solution. It passes every test and scores exactly par on every benchmark.

Each core moves P0 to P1.

aSC-2 standard

IN P0
OUT P1

bSC-2 standard

IN P0
OUT P1
CYCLES
120
at par
ENERGY
936
at par
NODES
2
at par
INSTRUCTIONS
4
at par