On 12/4/2017 5:46 PM, mugginsac wrote: > A big thank you to Charles for this design. I have ordered and received 3 > boards from OSH Park. > As I understand the schematic, this board uses both 5V and 3.3V power. Both > voltages appear to be provided through the P1 header. Is this correct?
Yes. The board gets it's power from the BBB. > It appears that W3 then selects the pull up voltage required by the > daughter card or BOB. Yes. The external I/O can be pulled up to 3.3V or 5.0V. > Not quite sure what purpose W1 and W2 serve. I know they look like they > pull pins 22, 23, 24 and 25 of the respective DB25 connectors to either +5 > or gnd. But when would they be used?? This is how Mesa does it. If you are using an IEEE 1284 parallel port cable or a DB-25 break-out-board that grounds all the IEEE 2384 ground pins, you need to connect those pins to ground on the DE0-Nano_DB25. If, however, you have a solid 5V supply and are using Mesa DB25 expansion boards, they can be powered via 5V supplied via the parallel port cable. -- Charles Steinkuehler [email protected] -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. Visit this group at https://groups.google.com/group/machinekit. For more options, visit https://groups.google.com/d/optout.
