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ワタリ

Watari is my Bangle.js watch.

specs
processorNordic 64 MHz nRF52832 ARM Cortex-M4
RAM64 kB
flash512 kB on-chip, 4 MB external
display1.3″ 240×240 16-bit LCD with two-zone touch
GPSUBlox UBX-M8130
HR sensorBD 1668
accelerometerKX023
magnetometerGMC303 3-axis compass
battery350 mAh 502527 Li-ion, 1 week standby
dimensions5×5×1.7 cm

positioning

Formula for positioning text at the center of the display (xc, yc), given the scale (s), number of characters (n), and number of rows (r):

w = n * 6 * s
h = r * 8 * s
x = xc - (w / 2)
y = yc - (h / 2)

For example, a 3-row, 5-character-wide text block at a scale of 2 should be positioned at [90, 108] to be centered.

w = 60 = 5 * 6 * 2
h = 48 = 3 * 8 * 2
x = 90 = 120 - (60 / 2)
y = 108 = 132 - (48 / 2)

There’s a calculator in the lab.