define and alias: code with names

sgt r1 r0 303.15 – what was r1 again? And why 303.15? In three weeks nobody knows. Two instructions bring order.

define: names for fixed numbers#

define LIMIT 303.15   # 30 C

Wherever LIMIT appears afterwards, the chip uses 303.15. A define costs no register and never changes. Perfect for set points, thresholds and later for device types.

alias: names for registers and pins#

alias temp r0
alias sensor d0

Now you may write temp instead of r0 and sensor instead of d0. An alias on a pin also shows up at the housing’s screws.

The layout that works#

# --- Heat warning ---
# --- 1. Settings ---
define LIMIT 303.15     # 30 C
# --- 2. Registers and devices ---
alias sensor d0
alias light d1
alias temp r0
alias hot r1
# --- 3. Main loop ---
start:
yield
l temp sensor Temperature
sgt hot temp LIMIT
s light On hot
j start

First define, then alias, then the main loop with yield. Every number you might want to tune later sits at the top with a comment – the body only contains names.