How to conect two kStep boards?

[yethsts]

How to power two kstep boards at same time? I know that the usb power is not enough for three boards: kFlop+1st kStep+2nd kstep. So I plan to power the kFlop using the JR1 +5v Power and remove the Jumper J3. And install all the JP34-35 of both kstep boards, and connect the JP36 of the first kstep to the Jp7 of kflop board by Robin cables. AND connect the J6 of the 1st kStep board to the J6 of the 2nd kStep board. In this case, the external power supply will give the electricity to KFlop via JR1, then to 1st KStep board via JP36, then to 2nd KStp via the J6. Is it right?

But I must alse use the usb cable to download and run the program, not via JTAG port. I wonder can I I remove the J3 and give the kFlop power via the JR1,not J1 usb, but still use the J1 usb to download and run the program? I think in this case there is no 5v power supply conflict because the USB is only for download and run the program, not for the power supply of the kFlop board. Am I right?

[TomKerekes]

Hi yethsts,

How to power two kstep boards at same time? I know that the usb power is not enough for three boards: kFlop+1st kStep+2nd kstep. So I plan to power the kFlop using the JR1 +5v Power and remove the Jumper J3. And install all the JP34-35 of both kstep boards, and connect the JP36 of the first kstep to the Jp7 of kflop board by Robin cables. AND connect the J6 of the 1st kStep board to the J6 of the 2nd kStep board. In this case, the external power supply will give the electricity to KFlop via JR1, then to 1st KStep board via JP36, then to 2nd KStp via the J6. Is it right?

Yes. Actually KStep uses very little +5V Power. USB can drive KFLOP and two KSteps in most cases. See also here.

But I must alse use the usb cable to download and run the program, not via JTAG port. I wonder can I I remove the J3 and give the kFlop power via the JR1,not J1 usb, but still use the J1 usb to download and run the program? I think in this case there is no 5v power supply conflict because the USB is only for download and run the program, not for the power supply of the kFlop board. Am I right?

The USB can be used regardless of whether you are using +5V supplied externally or from USB. If applying external +5V remove J3 to avoid having two power sources connected together.

HTH

[yethsts]

Thank you. I saw your two kStep connection diagram. I find in the diagram one Enable signal (J6) drive two kStep board at the same time. Can the IO of KFlop output enough current for a long time?

[TomKerekes]

I find in the diagram one Enable signal (J6) drive two kStep board at the same time. Can the IO of KFlop output enough current for a long time?

yes

[yethsts]

Ok. Thank you very much.