I have 3 circuitboards that I bought from TI, surplus. Happily, I also have schematics! Anyway, they are stepper drivers, which use the 297/298 chipset, and they drive my motors quite nicely.

I've got a problem, though. They have a 555 as an on board pulse generator. I need to convert the boards to step/direction input from my parallel port. It's a simple modification, but I just can't seem to get it to work right. (We've all had projects like that...)

Is there anyone in the North Texas area who would be willing to help me out? (Or anyone to whom I could send the boards for modification? It's a 5 minute job, if it goes right...)

I don't know why I can't do this project -- I should be able to do it in my sleep.

Anyway, HELP! I want to see my machine MOVE!

-- Chuck Knight

From what I gather from the datasheets you should be able to cut the traces connecting the 555 circuit that runs to pins 17 and 18 of the L297 and connect your Step connection to Pin 18 and your Direction Connection to pin 17 .

That should take care of it.

http://www.hvwtech.com/downloads/datasheets/l297_ST.pdf

Hi Chuck. I would like to know were to get this board for the stepper driver. I am in Argentina (South America) and here there is not much staff about stepper motors. I had made my own steppers drivers but they are not so "professional" (they are not chopper). I would be very pleased if you send me the info. Thanx a lot!

I got them at an electronics flea market in Dallas... Sorry, it was a one-time deal.

-- Chuck Knight