Would someone clarify the exact function of these Omega2 pins?



  • 'FW RST --- 38' is the Reset Input, active High and it can be directly connected to 3.3V (for example with a momentary button).
    Is this right?

    What is the other 'RST' pin?
    And what is the '3.3V --- VOUT' pin?

    Tnanks.



  • I would also be interested in clarification on these pins.

    My understanding is the FW RST will restore the Omega to factory settings if it is held high / low for 10 to 30 seconds. Tried earlier today and thankfully I couldn't get it to work as a found another fix for my problem.

    I have the latest firmware with the RST fix.

    What is the exact process for future reference?

    Home and Business Automation
    https://theCHARioT.co.uk

    0


  • FW_RST is a software based Reset driven by the Omega2 base code.
    RST, afaik, is a hardware reset (or halt.) My (previously) defect board had this pin tied to Gnd, which halted the board (only consumed 20 mA, and as cold as dead.)
    3.3V_out, is also known as NET_Power. The term is carried over from the original Omega (Omega 1.)
    Currently (at least in few boards I know of), they are kept as float (not connected.)**

    Original Omega1's NET_Power supplies 2V to AR9331's Ethernet MAC transformer's C.T. (center tap) as the chip's DC bias.
    It appears that MT7688 does not need external DC bias for Ethernet MAC, thus this pin is left open.
    I.e., there is no 3.3v output at this pin.

    ** There are two unpopulated zero-ohm resistor positions on the PCB for shunt. One of them, if short-circuited, appears to be able to supply 3v3.

    ccs_hello



  • @ccs-hello said in Would someone clarify the exact function of these Omega2 pins?:

    FW_RST is a software based Reset driven by the Omega2 base code.

    ccs_hello

    So it's purely software controlled? Why have a pin?

    Home and Business Automation
    https://theCHARioT.co.uk

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  • It is connected to an external push-button switch in a dock board.
    For example, during boot up process, trigger uboot firmware reflash.
    See https://community.onion.io/topic/1154/omega-2-usb-firmware-install-after-brick

    ccs_hello



  • Thanks @ccs-hello so the Power dock suggests holding the FW_RST for 10 seconds will restore the factory firmware. Doesn't indicate if this is held high or low but presumably it can be done without the dock.

    Home and Business Automation
    https://theCHARioT.co.uk

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  • Normally 0V, When pressed, about 2.1v as logic high.



  • Just wish to mention that if you use a dock-less setup and just provide 3.3v power on Vcc and Gnd pins.
    This two-wire arrangement would work.
    I.e., one can just leave these three pins (FW_RST, Reset, and NET_PWR) open / not-connected without affecting Omega 2's operation.

    ccs_hello



  • A bit explanation on Net_Power (not connected)
    https://community.onion.io/topic/1914/help-getting-ethernet-configuration-correct/9

    ccs_hello


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