# Sand table settings. Anything left out uses the default in sandtable/config.py.

[serial]
port = "auto"          # or e.g. "/dev/ttyACM0" (Uno) / "/dev/ttyUSB0" (CH340 clones)
baud = 115200

[controller]
type = "grbl"          # "grbl" = Arduino Uno + CNC shield; "fluidnc" = the custom ESP32 board

[machine]
rho_max_mm = 133.0     # how far out the ball goes (the tray reaches 133 mm)
invert_theta = false   # set to true if test_f draws a mirrored F
theta_offset_deg = 0.0 # turn every pattern by this much

# CNC shield DRV8825s at 1/32 (M0, M1 and M2 jumpers all fitted, 2026-10-31).
# Only M2 fitted (1/16) measured as 35.556 / 80.
theta_steps_per_deg = 71.111
rho_steps_per_mm = 160.0

[motion]
ball_speed_mm_s = 25.0 # drawing speed; slower = crisper lines and quieter
max_theta_deg_s = 60.0 # arm spin limit (10 rpm)

[erase]
enabled = true
pitch_mm = 7.0         # spiral spacing between patterns (the ball is 9.5 mm)
speed_mm_s = 35.0