write_scratchpad(9)

🌸 write_scratchpad(9) — Kernel API Manual 🌸

okay so bestie, welcome to write_scratchpad(9) from the Kernel API Manual — yes that's the manpage name, we're being ✨official✨ today. This is the little function that writes bytes into the device RAM and honestly? iconic behavior. Let's get into it 💅

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✨ NAME ✨

write_scratchpad — writes nb_bytes in the device RAM. that's it, that's the whole vibe 🎀

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✨ SYNOPSIS ✨

int write_scratchpad (struct w1_slave *sl , const u8 *data , u8 nb_bytes
);

literally the whole signature, copy it exactly, don't get creative with it 🫶

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✨ ARGUMENTS ✨

• sl — pointer to the slave you wanna write in 💖 like, the target. the main character of this operation.
• data — pointer to an array of 3 bytes, because 3 bytes MUST be written. no exceptions, no shortcuts, not me being dramatic — it's literally in the spec 😭
• nb_bytes — how many bytes get written: 2 for DS18S20, 3 otherwise. so like, DS18S20 is the special one and everyone else gets three 🦋

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✨ RETURN ✨

• 0 if success ✨ slay
• -kernel error code otherwise 💀 (it's a kernel error code — not your usual errno situation, don't @ me)

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✨ SEE ALSO ✨

Kernel file ./drivers/w1/slaves/w1_therm.c struct — yes the whole struct, they said what they said 🎀

And the full friend group, no one left out:

• w1_therm_family_converter(9)
• struct w1_therm_family_data(9)
• struct therm_info(9)
• reset_select_slave(9)
• convert_t(9)
• read_scratchpad(9)
• copy_scratchpad(9)
• recall_eeprom(9)
• read_powermode(9)
• trigger_bulk_read(9)
• w1_therm_add_slave(9)
• w1_therm_remove_slave(9)
• w1_DS18B20_convert_temp(9)
• w1_DS18S20_convert_temp(9)
• w1_DS1825_convert_temp(9)
• device_family(9)
• bus_mutex_lock(9)
• check_family_data(9)
• bulk_read_support(9)
• conversion_time(9)
• temperature_from_RAM(9)
• int_to_short(9)
• w1_poll_completion(9)

like, read read_scratchpad(9) next, it's the sibling, they come as a set 👑💜

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ngl the 3 bytes MUST be written thing is the one rule you cannot fumble. your data array is 3 bytes. periodt. 🙈

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and that's the page!! source path is ./drivers/w1/slaves, version date is October 2026, and the page itself is write_scratchpad(9) — mwah, bye bestie, go write some scratchpad 💖🌈⭐