On Sun, 9 Sep 2001, Rick Engebretson wrote:

> I'm trying to rediscover how to control the RS232 UART every PC has two
> of. This powerful interface could be more useful, particularly for
> process control or robotics. I'm not looking for a driver, unless it is
> highly versatile.
>
> In the original PCs one simply input or output to the UART BIOS address
> and the bit field was yours. The DOS driver for the COM ports began the
> process of hiding control by adding a new layer.
>
> Pascal and C can be used to build drivers, such as the terminal driver or
> modem driver.
>
> I am hoping someone in this group has some experience with this in Unix
> (Linux). I've reinvented the wheel plenty of times.
>
Apart from the documents previously provided, I would recommend that
if you need capabilities that are not provided by the serial driver
already that you:

1. Apply a realtime scheduling patch, you are probably going to need it.

2. Write your custom control functions as an extension to the existing
   serial driver. This prevents needing to write a complete custom serial
   driver, and the resulting module/patch would likely be useful to anyone
   else trying to do robotics under Linux. It also allows you to completely
   separate the serial control functions from the robot control logic, making
   your control program easier to write and maintain.

-- 
Daniel Taylor