On Thu, 10 Jan 2002, Adam Majer wrote:
> On Thu, Jan 10, 2002 at 10:56:59PM +1100, Matt Chipman wrote: > > > > > > > Hi all, > > > > > > I have a 486 with 1 byte serial FIFO. This means if I transfer stuff > > > through my modem, I get a bunch of bits lost when HD trasnfer any > > > data. To fix the problem I unmasked IRQs on the HD controller. > > > > > > > > > I could be way off the mark here but when your system boots, does it > > say 2 x serial ports 16550 UART ? > > > > If not replace your serial/hd controller with a 16550 uart model > > > > -Matt > > It's a 16450 UART [or something like that]. Hence 1 byte FIFO instead of > 16 byte FIFO. > > If the interrupts were unmasked properly then I wouldn't need to get new > hardware... As I said, it works in 2.2.x series... > > - Adam That, even if you think of replacing the io card, its very likely that you dont find 16550A UART's available. I have several, all of diferent manufacturers, and none is a 16550; instead they r 16450. Did you check if the interrupts are correctly assigned to the serial ports? with irq=0, the serial ports will be pooled instead of relying on their irq lines. If you pool with a eavy processor load, characters will be lost. I dont know if this can help you, but i hope so. Maybe you can give us some more information. I remember reading somewhere that the serial driver does not assign irq lines to serial ports, it only identifies hardware. To do that ( assign irqs ) you must configure /etc/serial.conf and run setserial. Its up to with setserial to assign each device ( /dev/ttySx ) to each hardware physical port. Usualy setserial will be run at start up, thus configuring the irq lines; but for testing do the following: $setserial /dev/ttySx will give you the status of the device. an example is: $setserial /dev/ttyS0 irq 4 J.A.Serralheiro
