Robotics and parallel ports

[c d saunter]

Isaac T Alston (sleepingeliminator at gmail.com) wrote:
: Heiko Wundram wrote:
: > Maybe it's what you're looking for.

: Thanks for that. I've never actually built a robot or anything like that
: before, so I'm welcome to any advice I can get! I've heard programming via
: USB is hard, so that's why I'm using the parallel port (serial ports are
: said to be slow when sending a lot of data (I think)). I think I'll start
: off with something very simple, for example controlling a motor and then
: move up to more advance models.

Greetings Isaac,

Go for it!  Words of advice on using the parallel port:

1 - there are different modes (SPP, EPP etc.)  availible - 'Parallel Port 
Interfacing' on www.beyondlogic.org is an excellent starting point.   The
mode is set in the PC BIOS, and if it's not set to the mode you're coding
for then you may spend hours being perplexed...

2 - If you're new to robotics etc. make sure you think carefully about
how you connect your motors to the parallel port to prevent hardware
getting blown...  An old but good book that covers electronic (and
computer) control of motors is "The Robot Builder's Bonanza"

Seperatly: USB needn't be so hard...  This little board of tricks
http://www.dlpdesign.com/usb/usb245.shtml gives you a parallel interface
from USB 1.1, and a C library on the PC (which can be accessed from 
Python with ctypes) - data rate is similar to the parallel port, although
latency is much higher, which can kill performance of some applications.

Enjoy!