Talk:Melzi

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Is it possible to saw off those 4 stepper drivers? I miss a fifth stepper driver and a support for milling also. --IRBaboon

  • Judging from the PCB images, you could remove the X/Y/Z relatively easily with straight vertical cuts. The right edge of E overlaps with other traces, though. Sparr 03:03, 20 November 2011 (UTC)

  • Have you thought about the AT90USB1286 for the chip? Its specs are mostly comparable to ATmega1284p (a few fewer ADCs but it still has 8) and has integrated USB, and is a lot better than the ATmega32u4 from Arduino Leonardo.
  • Also, are the endstop pullups (R24, R25 and R26) really necessary? Why can't we rely on the AVR's internal pullups?
  • Have you thought about replacing the trimpots with a digital potentiometer? As far as I can tell, it would be cheaper - you can have a quad digital pot for around $1 in 100 piece quantities, while a trimpots often cost that much a piece.

--Guan 19:59, 5 March 2012 (UTC)

Why are the thermistor bias resistors 10K? 4K7 is the norm and lower would be better for accuracy at the top end with 100K thermistors.

--Nophead 18:34, 23 March 2012 (UTC)

  • This has been fixed in the Melzi 2.0 board. --FlyingLotus1983 (talk) 19:51, 23 March 2014 (PDT)