PIC/297/298 WEIRD MOVEMENT, It will jus take a minuit. THANKX.

[ellasaro]

Hi,

I'm having this problem maybe someone can give me some useful ideas.

I have a PIC controlling two L297 - L298 (each L298 is connected to a stepper of course).

This is how it basicaly works:

1) a rabbit sends to the PIC, via serial port, the direction in which the steppers must move
2) the PIC updates the ENABLE and CW/CCW of the 297
3) the PIC then generates the CLK for the steppers to move

The problem is that if I program the PIC to generate 20 CLK pulses for each time it recieves a new direction it works fine, BUT IF I PROGRAM IT TO GENERATE 1 OR EVEN 10 IT JUST MOVES ERRATICALLY.

Am I being clear about the problem I'm having?
Any ideas? Could it be mechanic or it looks more like a software issue?

THANX TO ANY INSIGHT YOU MAY OFFER!

[neilw20]

Wiring or earthing problems introducing noise on input signals?

Long wires, daisy chained power wires, shielded leads - only terminate one end of shield.

Power supply ripple introduced to logic side of power through poor common wiring.

Post some pictures of all of the wiring and setup.