Re: Cyclom 16Y on pentium 200Mhz

Marcio Saito (
Thu, 06 Feb 1997 17:39:20 -0800


For faster response, next time, please send configuration/
installation questions about Cyclades products to

Arnaldo Carvalho de Melo wrote:
> Do you received any report on problems using a cyclom 16Y on a pentium
> 200 Mhz???

No, there are no known compatibility problems between the Cyclom-Ye
and any motherboard (I'm assuming you are refering to the Cyclom-Ye
with 16 ports and not to the obsolete Cyclom-16Y).

> We put together a system using linux kernel 2.0.27 (the one
> that came in RedHat 4.1) a Adaptec 2940AU PCI SCSI card and a Realtek
> based PCI network card and a PCI SVGA card (trident 9440), disabled PnP on
> bios and put all irqs below 13 to "ISA legacy", we are using the correct
> major/minor numbers and put the driver directly in the kernel (static, no
> module for cyclades.c).

Reserving all IRQs below 13 for ISA cards doesn't leave many
IRQs for your PCI cards. Make sure you have enough IRQs allocated
for ISA and PCI cards.

> The board freeze sometimes during the boot
> sequence and sometimes goes on but minicom can't talk with /dev/ttyC?, any
> ideas??

The board freezes? Or is the system that freezes?

If the system is freezing during the boot process, it doesn't mean
that it is a problem with the Cyclom-Y :).

Verify if the IRQ issue above is not what is causing the problem.
The default IRQ used by the Cyclom-Y cards is IRQ10.

Make sure that there are no address/IRQ conflicts between the
boards in your system. The default memory address used by
the Cyclom-Y cards is 0xd4000. The Cyclom-Y doesn't use I/O
port addresses.

If there are no conflicts and you still supect of a problem
related to the Cyclom-Y board, please run CYCTEST (available
at and contact
<> (or our local distributor).

Technical support from Cyclades is unlimited and free to all
Cyclades customers.

> BTW I looked in drivers/char/cyclades.c and there's a
> CYCLOM_16Y_HACK... could be this??? Just defining this it does a udelay
> (10L) in cy_interrupt(int irq, void *dev_id, struct pt_regs *regs), could
> be that the machine is too fast and we must enable this to sync or
> something???

This is a hack to workaround a problem that we found in a old model
(dicontinued a couple of years ago) of the Cyclom-Y (a 16-port model,
not expandable). If you have one of those boards, please contact the
local Cyclades distributor to update your hardware.

> Arnaldo Carvalho de Melo
> Conectiva Internet Solutions



Marcio Saito e-mail:
SW Engineer/Product Manager phone: (510)770-9727 x214
Cyclades Corporation fax: (510)770-0355