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bigtreetech / BIGTREETECH-SKR-V1.3

32bit board with LPC1768, support marlin2.0 and smoothieware, support lcd2004/12864, On-board TMC2130 SPI interface and TMC2208 UART interface no additional wiring is required
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Max voltage for ABL and auto power pin? #13

Open tilkor opened 5 years ago

tilkor commented 5 years ago

Hello, I was looking under the pin group and I didn't see a pin specific for "auto power off after print", I am assuming that PS_ON_PIN?

I am using an inductive z probe and I wanted to know the max voltage the Z-min pin can handle?

Thanks!

Alissonverd commented 5 years ago

@tilkor I'm trying to request a pin header to next version of this board. Maybe you could help with my request, we need show to @bigtreetech how it's important.

https://github.com/bigtreetech/BIGTREETECH-SKR-V1.3/issues/16#issue-435716653

ghost commented 5 years ago

I sent them a message via AliExpress a while back about wasting 5 pins on the TxD to TMC2208, because the software serial code that is used in LPC MCU's in Marlin doesn't need the TxD pins, it works in single pin mode (RxD pin only) if you specify the same pin for RxD and TxD, but the people behind the SKR board design have not made this a possibility, though you can modify the board yourself, but so easily fixed if the SKR designers would listen, thus providing 5 free extra pins for the user to use as they so wish,

Also, those people not using TMC2208's have those 5 pins sitting there doing absolutely nothing, with no physical easy access to them (a pin header).

You can gain access to those 5 pins if you have steady hands/fingers and SMD soldering abilities, and fit a 5 pin header to the board yourself. I superglue mine to the board as you can't go drilling through multi-layer boards, you don't know what tracks are where on the inner copper layers etc.

LongLiveCHIEF commented 5 years ago

I'm not familiar with non-Marlin firmware, but I'm wondering if it was designed this way for smoothieware or klipper?

tilkor commented 5 years ago

yeah, I have maxed out the board and had to do some creative work around to get the PS_ON working. Since the chip can only put out something around .09w of power, I ended up using a low/high SSR that draws very low amps to trigger my larger SSR that handles power to everything.

I would also post on the Bigtreetech facebook page.