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New P2 module

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  • evanhevanh Posts: 16,677
    edited 2025-08-29 09:57

    @Wuerfel_21 said:

    @evanh said:
    The only way to use a SD card, and not be constantly removing it, and also develop new code via serial booting is to have a loader in the EEPROM. Thereby entirely bypassing the ROM's SD boot solution.

    I usually just set the pullup for the long serial window. Forget which one that was. That will never auto-boot anything, but that's usually desireable.

    P59 pull-up forces serial only booting. P59 pull-down forces no serial booting.

    Yeah, I suppose that is an option: Boot from serial as a loader until happy with finished product, then put the loader on the SD card and make it bootable.

  • RaymanRayman Posts: 15,554
    edited 2025-08-29 12:35

    @evanh Looks like that was it...

    FatFS works from boot with this change to line 550 in sdmm.cc:

            //spm_rx |= P_SYNC_RX | P_OE | P_INVERT_OUTPUT | P_HIGH_15K | P_LOW_15K;  // rx smartpin mode, with 15 k pull-up
        spm_rx |= P_SYNC_RX | P_OE | P_INVERT_OUTPUT | P_HIGH_1MA | P_LOW_FLOAT;  //  pull-up
  • evanhevanh Posts: 16,677
    edited 2025-08-29 14:32

    You do know that's a work-around, right? It overpowers the incorrectly wired R24 pull-down on P58 that should be a pull-up. I expect you to correct the schematic and fix the already made modules in the medium term.

    PS: The only reason, I think, that FSRW works for you is because you're using the broken sdspi_bashed2.spin2 driver that doesn't ever do a card busy check. Which is also why FSRW needs multiple attempts to get anything done.

  • RaymanRayman Posts: 15,554
    edited 2025-08-29 14:51

    @evanh what’s wrong with the work around?

    Not sure how changing the pulldown would affect other parts sharing that pin…

  • evanhevanh Posts: 16,677

    @Rayman said:
    @evanh what’s wrong with the work around?

    It ain't gonna be standard issue for a starters. It'll be up to you to add the workaround each time there is an update to includes.

    Not sure how changing the pulldown would affect other parts sharing that pin…

    The pull-down is a mistake. A tad surprisingly, the Parallax board have no resistor at all. So my programmed pull-up is actually needed.

    Everything except the CLK requires a pull-up.

  • evanhevanh Posts: 16,677
    edited 2025-08-29 15:29

    The fact that the Eval and Edge boards have no pull-up resistor present on P58 means you can remove the Swap's R24 and be reasonably confident of future drivers always handling it.

  • RaymanRayman Posts: 15,554

    @evanh Have to see how that would affect the behavior of the PowerGood1 LED...

  • evanhevanh Posts: 16,677

    Pull-ups on the LEDs don't matter but I have no idea what the PGOODx pins will do from that regulator. One hopes they go hi-Z when good. My gut reaction is cut those tracks so that P58/P59 no longer reach the regulator chip.

  • RaymanRayman Posts: 15,554

    @evanh Don't think I'll be cutting any traces..

    R24 is in an easy place to remove though. I'll try that.

  • evanhevanh Posts: 16,677

    Goes without saying that future board production runs should be changed to fix these issues.

  • RaymanRayman Posts: 15,554

    Removing R24 seems to make FatFS happy. But, it turns off the associated LED that was kind of using as power LED.

    Tried flashing this to get it back:

    con  'Flashing this erases the uSD

PUB main()
  wrpin(58, P_OE|P_LOW_15K)
  pinl(58)
  repeat

    But, this seems to have the effect of erasing the uSD. So, not doing that...

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