Controller BB voltage

Does anybody know the output voltage from the sb25 connector on the 1f bb controller? Still having the "Disconnected " message when plugging my PWNcnc spindle.

Hey Angel,

most of the 25-pin I/O port connector pins are directly connected to the AVR (ATXMEGA192A3U (datasheet)) on the AVR board, so are 3.3 V. Regarding pins 13 and 14 for the Modbus serial communication interface, there is a ISL83485 RS-485 Transceiver running with 3.3 V supply that can deliver -8V to +12.5V, with a Bourns SRF2012A-121YA common mode inductor on these two pins.

Regarding the “Disconnected” message you’re encountering with your PWNcnc spindle, this could be due to several issues. It’s important to ensure that the plug is seated properly and that there are no connection problems with the breakout board adapter. Additionally, swapping the RS485 + and - wires around might resolve the issue if they were initially connected incorrectly. If these steps don’t help, it might be necessary to check the controller for connectivity issues or consider resoldering the solder joints on the D-Sub connector pins on the Onefinity Controller Mainboard

1 Like

Your setup with the ATXMEGA192A3U microcontroller directly connected to the I/O port pins operating at 3.3V is consistent with the specifications of these components. Best price Graphisoft ArchiCAD 26. The ISL83485 transceiver’s ability to deliver a wide range of voltages (-8V to +12.5V) makes it suitable for the differential signaling required for RS-485 communication, and the Bourns inductor on pins 13 and 14 will help in maintaining signal integrity by suppressing common-mode noise.