Ken Johnson wrote: > > Hi, I have been trying to drive my pcb drilling machine using the parallel > port of a toshiba T1100 (old, but cheap) and have run out of ideas so I > thought I would tap the vast knowledge and experience of the people on the > list. I'ts not that OT really, I will be using a pic to monitor the limit > switches once I have sorted this problem out. > I am using 2 bits of the port to drive each of the two motors, but no > matter which way I talk to the port (lpt1) it doesn't work. I have tried > OUT, LPRINT, and the print character service (INT17, service 0)- all work > ok on my pentium but not on the T1100. If I hook up my printer to the > T1100, I can print ok so the port is working. A test program reports the > lpt port as H378 (lpt1), but just in case I tried lpt2 +3- still no good. Maybe the parallel port on the T1100 is not a standard one, and it is only pretending to have it at 0x378. The easiest solution is probably to have the circuitry external to the PC generate an ACK pulse for every strobe that it receives, thereby emulating a real printer. It might be enough just to connect the /strobe to /ack. When wired like this, all you need is a program that sends data to the parallel port through normal means, i.e. DOS file handle 4 or INT 0x17. Frank ------------------------------------------------------------------------ Frank A. Vorstenbosch Phone: 0181 - 636 3000 Electronics and Software Engineer Mobile: 0976 - 430 569 Eidos Technologies Ltd., Wimbledon, London Email: fav@eidos.co.uk