Machsupport Forum

Mach Discussion => Brains Development => Topic started by: iceblu3710 on May 13, 2009, 03:44:41 AM

Title: My Binary Parallel Port Expander
Post by: iceblu3710 on May 13, 2009, 03:44:41 AM
Hi all, Ive got a brain problem:

I have attached my brain files as their an pain in the ass to make click at a time but in the files LPT_BCD_6-10 and LPT_BCD_16-20 the lines that handle Output #10 and Output #20 the and logic blocks are on be defualt all the time for me. Its the exact same process I made the other 18 and yet its only out 10 and 20 that are always on. Are these outputs used by Mach3 already or something?

If they are I can get a max of 16 on BCD and use the last port as E-Stop as adding it to the BCD will only add one anyways.

My 2nd question is I believe the data on the parallel port is polled ever what 40us? if thats so then running Mach at 35kHz is ~3us pulse train so your motors have a chance to run ~14 extra steps before reacting to an input. Is that all right? If so I will need to find a 4:16 or 5:32 BCD chip that operates >= 25kHz

I will post my entire project ones Ive got it mostly working for those who are interested, thanks!

NOTE: I found a way around the max 50 rungs and the inputs get stuck highlighted, just select two, add, and choose FORMULA. after you click cancel you can deselect anything you want!