OWSBM(4)

💖 NAME 💖

Okay bestie, gather round: this is the OWSBM(4) page from the kernel interfaces manual, and it's all about the owsbm 1-Wire smart battery monitor device. Slay. 🔋✨

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🎀 SYNOPSIS 🎀

owsbm* at onewire?

🌸 DESCRIPTION 🌸

The owsbm driver provides support for the 1-Wire smart battery monitor. No cap, this little sensor is stacked: it possesses a temperature sensor, an A/D converter for measuring both battery voltage and current, a current accumulator of both incoming and outgoing current, an elapsed time and 40 bytes of nonvolatile EEPROM. It's giving tiny powerhouse energy. 💅

Only the three voltages (VDD, VAD, CR) and temperature are accessible by the sysctl(8) interface. That's the vibe check on what you can get at through sysctl(8) — literally just those three voltages and temperature.

The following chips are supported by the driver:

• Maxim/Dallas DS2438 — the one and only chip on the guest list, bestie. 👑

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⚡ MEASURING CURRENT ⚡

The sensor does not measure current directly. Instead it measures the voltage across the Rsens pins. The way that works is:

I = Voltage CR / Rsens    (where Rsens is in Ohms)

So yeah — voltage across Rsens, then that formula. Keep Rsens in Ohms, periodt. 🧚

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🦋 SEE ALSO 🦋

• intro(4)
• onewire(4)
• owtemp(4)
• sysctl(8)

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💜 HISTORY 💜

The owsbm driver first appeared in OpenBSD 4.1. A little retro, a little iconic. 🌈

👑 AUTHORS 👑

The owsbm driver was written by Aaron Linville <aaron@linville.org>. Respect the author, bestie. 🫶

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okay bye bestie, this OWSBM(4) page is brought to you by Debian, dated July 16, 2013 — mwah 💋✨