IBCAC(3)

✨ IBCAC(3) ✨

ok so bestie, welcome to Traditional API Functions — this is the ibcac page and it is giving low-level GPIB realness 💅

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🌸 NAME 🌸

ibcac — assert ATN (board)

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🎀 SYNOPSIS 🎀

#include <gpib/ib.h>

int ibcac(int ud, int synchronous);

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💖 DESCRIPTION 💖

ok so here's the tea ☕ — ibcac() makes the board you picked with the board descriptor ud become the active controller by asserting the ATN line. iconic behavior, honestly.

⚠️ but listen — the board must be controller-in-change in order to assert ATN. no cap. that's the vibe check it has to pass.

now about that second arg: if synchronous is nonzero, then the board will wait for a data byte on the bus to complete its transfer before asserting ATN. very patient of it, we love a board that waits its turn 🫶

if the synchronous attempt times out, or if synchronous is zero, then ATN will be asserted immediately. no waiting, just send it 😤

and now the part nobody tells you: it is generally not necessary to call ibcac(). it's provided for advanced users who want direct, low-level access to the GPIB bus. so like… if that's you, slay 👑 if that's not you, maybe don't, iykyk 🙈

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⭐ RETURN VALUE ⭐

the value of ibsta is returned. that's it, that's the whole answer, periodt 💅

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🌈 COPYRIGHT 🌈

Copyright © 2003-2006, 2008 Frank Mori Hess

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ok bye bestie 💖 this was the IBCAC(3) page from linux-gpib 4.3.7, dated 07/06/2026 — go assert some ATN responsibly, muah 🎀✨🦋