Re: [misterhouse-users] Having problems with RS232 interface

[<Bbi...@ao...>]

Hi Gary:

In a message dated 2/16/00 9:15:52 PM Central Standard Time, 
gb...@te... writes:

> I'am using a Cyclades Cyclom-Y Multiport Serial Board.
>  It maps 8 serial ports through 1 interrupt, the
>  board comes with it's own device driver for all the
>  COM ports.

Aha. You probably also have a setup program to adjust buffer sizes
and priorities on the board and in the driver. Look at the users' manual.

>  I have been using the board for over a
>  year and half now with no problems.  As I said in
>  my previous e-mail, I have stand-alone programs that
>  work with no problem with the serial ports.

Simultaneously?

>  The operating system that I'am using is Windows-98.
>  
>  Here are the specs on the serial ports for the devices.
>  
>  weather computer(heathkit id5001) : 9600 baud, 8 data bits, 1 stop bit, no
>  parity
>  HCSII : 9600 baud, 8 data bits, 1 stop bit, no parity
>  Timecommander-plus : 2400 baud, 8 data bits, 1 stop bit, no parity

I'm not sure how mh handles the Timecommander. On the CM11, it will
try to finish up an operation before going on to the next Serial_Item - which
can mean waiting during a retry or fetching data before a write. You can
probably increase the buffer sizes in the driver (there are SerialPort methods
to do that - see buffers() in the docs). The card can probably be changed as
well.

>  The HCSII is sending the most data to misterhouse.  I would estimate
>  that it is sending about 100 bytes per second to the program.

Set interrupt queue size (on the card) as high as practical. You really don't
want 100 interrupts/secord - a multiport handler has some per-interrupt
overhead.

-bill