SCMDI2C(4)

💅 SCMDI2C(4) — the Kernel Interfaces Manual page, but make it make sense 🎀

ok so bestie, this is scmdi2c, section 4 of the Kernel Interfaces Manual, and it is literally the glow-up era for talking to a motor driver. sit down, grab a boba, we're going in 🧋✨

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✨ NAME ✨

scmdi2c — the I2C frontend to the Sparkfun Serial Controlled Motor Driver. yep, that's the whole vibe. it's the little connector piece that lets your kernel chat with the SCMD over I2C 🦋

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🌸 SYNOPSIS 🌸

scmd* at iic? addr 0x58
scmd* at iic? addr 0x59
scmd* at iic? addr 0x5a
scmd* at iic? addr 0x5b
scmd* at iic? addr 0x5c
scmd* at iic? addr 0x5d
scmd* at iic? addr 0x5e
scmd* at iic? addr 0x5f
scmd* at iic? addr 0x60
scmd* at iic? addr 0x61

ten whole addresses, bestie. 0x58 through 0x61, all lined up like a little squad. pick your fave, they're all valid 💖

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👑 DESCRIPTION 👑

okay so here's the tea ☕ — the scmdi2c driver provides the I2C frontend attachment for the Sparkfun SCMD device. that's it, that's the job. it's the I2C-flavored side of the operation, the frontend, the vibe liaison. it's giving "I'm the connector, not the whole personality" and honestly? respect 🫶

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⭐ SYSCTL VARIABLES ⭐

the following sysctl(3) variables are inherited from scmd(4). yes, inherited. like a hand-me-down but make it kernel 🧚

• hw.scmd0.debug — if the driver is compiled with SCMD_DEBUG, this node will appear, and you can use it to set the debugging level. no SCMD_DEBUG? no node. that's the deal 🙈

lowkey important: this node only exists when SCMD_DEBUG was compiled in. don't go looking for it otherwise, you'll just be confused and sad 😭

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🎀 FILES 🎀

• /dev/scmdu — character device allowing access to the register space of a main u, SCMD device. that's your backstage pass to the registers, slay 💅

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🔥 SEE ALSO 🔥

run don't walk to these besties:

• iic(4)
• spi(4)
• scmdi2c(4) (yes, it references itself. main character energy, we stan 👑)
• scmdspi(4)
• scmdctl(1)
• sysctl(8)

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🌈 HISTORY 🌈

the scmdi2c driver first appeared in NetBSD 10.0. a debut. an era. periodt ✨

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💜 AUTHORS 💜

the scmdi2c driver was written by Brad Spencer <brad@anduin.eldar.org>. thank you for your service, king 🫡💖

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aaaand that's the page, bestie 🦋 ngl this one was short and sweet and I am obsessed. this little writeup is from the scmdi2c(4) page as shipped on Debian, dated December 1, 2021 — so if you're reading it later, hi from the past, hope your I2C bus is termination-happy 🎀💀✨