CY(4)

✨ NAME ✨

okay so bestie, this is CY(4), straight out of the Kernel Interfaces Manual — the man page for the cy driver: the Cyclades Cyclom-{4, 8, 16, 32}Y asynchronous comms board serial device driver. It’s giving niche-hardware main character energy, and honestly? Obsessed. 💅

🛠️ SYNOPSIS 🛠️

Here’s how it shows up in the kernel config, no cap:

cy0 at isa? iomem 0xd4000 irq 12
cy* at pci? dev ? function ?

That’s the whole vibe. Periodt. ✨

💖 DESCRIPTION 💖

This driver provides an interface to Cyclades Cyclom-4Y, Cyclom-8Y, Cyclom-16Y, and Cyclom-32Y asynchronous multiport serial boards. These boards are based around Cirrus Logic CD1400 communication controllers — that’s the lore, iykyk. 🦋

The device minor numbers for this driver are encoded like this:

d c c p p p p p     - bits in the minor device number

So the bits mean:

• ppppp — physical serial line (i.e. port) to use:
  • 0-3 on Cyclom-4Y
  • 0-7 on Cyclom-8Y
  • 0-15 on Cyclom-16Y
  • 0-31 on Cyclom-32Y
• cc — card unit number; note this limits the driver to four cards per system
• d — set to use as a dial-out line

Like, that’s the whole encoding situation, and it ate. 🎀

🌊 FLOW CONTROL 🌊

The cy driver makes use of the CD1400’s automatic CTS flow control. In addition, the CD1400’s automatic input flow control can be used. But it requires the kernel configuration option CY_HW_RTS and a special cable that exchanges the RTS and DTR lines — so don’t forget the cable, bestie. 🫶

🚨 DIAGNOSTICS 🚨

When things get messy, you might see this:

cy%d: port %d: can't allocate tty  There is not enough memory to allocate tty data structures.

Translation: there is not enough memory to allocate tty data structures. 😭

And also this:

cy%d: can't allocate input buffer  There is not enough memory to allocate the data input buffer.

Translation: there is not enough memory to allocate the data input buffer. 💀

Additional debugging output can be turned on with the kernel configuration option CY_DEBUG. Diagnostic counters may be enabled with the kernel configuration option CY_DEBUG1. Debug girlies, this one’s for you. 🔥

👀 SEE ALSO 👀

• termios(4)
• tty(4)

Go read those if you want the full tty lore. 📚✨

🫶 AUTHORS 🫶

The cy driver was written by Timmo Rossi. Credit where credit is due, periodt. 👑

💀 BUGS 💀

⚠️ Support for the Cyclom-32Y has not been tested.

Bestie, that’s the bug note. That’s it. That’s the whole vibe check. 💀🙈

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okay that’s the whole CY(4) page, bestie — this one came from Debian, dated November 10, 1997. slay 💅✨