On Sunday 13 December 2020 02:35:24 John Dammeyer wrote: > The problem with the boards are that they are a little too general > purpose. So much more is needed above and beyond isolated outputs or > inputs. > > For example, say you want RS485 for the spindle controller. Or maybe > CANopen CAN bus for pick and place tools to bring in raw material and > remove finished goods. Even just a tool changer. > > The Beagle has CAN bus and Serial ports along with I2C and SPI. These > should be configured so it's possible add an LCD display with touch > screen. If they make one of the CAN pins a switch input then the CAN > port is lost. That's what happened with the 4D Systems LCD cape I > bought (now discontinued). Useless if I also want a CAN cape. > > A cape meant for CNC should know that LIMIT and ESTOP switches should > be NC type for safety. So no disabling outputs with the ESTOP signal. > > A hardware PWM module on the Beagle should be an output. And > ideally, with a jumper, a PWM to 0-10V output or else STEP with the > corresponding DIRECTION signal. > > Inputs tied to the AB and Index input of one of the quadrature encoder > modules. > > Ultimately what's more cost effective and saleable? A general purpose > board that still needs another BoB or a dedicated interface that would > work with _most_ mills or lathes. > > IMHO the latter. > > John
While I would argue (gently) in favor of the former as it often has leds to let you actually see the input for setup and signal tracing purposes. Encoder inputs in particular can often only be accessed by the data they generate. If they fail, where did it fail can be harder to nail down in the dedicated case. Not a showstopper, but the added complexity being hodden sure doesn't make it easy. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
