diff --git a/Board.jpg b/Board.jpg index 47e1b22..dcfe9c8 100644 Binary files a/Board.jpg and b/Board.jpg differ diff --git a/README.md b/README.md index e73a740..37b042a 100644 --- a/README.md +++ b/README.md @@ -4,29 +4,23 @@ A very small 3D printer board for use on a toolhead. It is designed to be used w ![Image of Board](Board.jpg) Features: -* TMC2209 driver -* STM32F042C6T6 +* TMC2209 stepper driver +* STM32F103 72Mhz MCU * Two MOSFET drivers fans * One bigger MOSFET driver for a hotend heater * Thermistor input * One endstop * CAN bus +* USB Main power is 12-24V. 24V is preferred to keep the currents low -The CAN Bus is not terminated, instead it uses 4 wires, termination should be done at the other end. +All done in KiCad and open source. -It uses an external 3.3V switch regulator. - -All done in KiCad - -Possible issues: - -* Is the cooling for the TMC2209 adequate? Seems to be, the board reaches about 50C under the TMC2209 when running a small stepper at 1A. Change ideas: -Is the endstop useful? Could be used as a filament runout sensor. +* Find a better heater mosfet, our 3.3V Vgs is on the low side for that chip. --- @@ -36,17 +30,17 @@ First prototype production run is done. ![First board](FirstPic.jpg) -The board works mostly as intended. Some quick tests shows that the MCU can run klippy, stepper drivers, fan drivers and thermistors works perfectly fine. +They work! 2020-05-29: ![Test setup](TestSetup.jpg) -After a lot of software work and many hours of testing I can report that everything actually works as intended (except one resistor that should have been 1k was a 10k) +After a lot of software work and many hours of testing I can report that everything actually works as intended (except one resistor that was a 10k insteadof 1k) * The thermistor input gives a very low noise signal, even at high temperatures. * Endstop works -* All mosfet outputs works with reasonable loads (2A at 24V). I do not have a dummy load for very high load testing, but a heater on the FAN connectors and a hotbed to the heater connector... +* All mosfet outputs works with reasonable loads (2A at 24V). I do not have a dummy load for high load testing, but a heater on the FAN connectors and a hotbed to the heater connector... * The thermals of the TMC2209 seems ok. With no cooling fins or active cooling it reaches 60C (top and bottom) when mounted close to a hot stepper. I should test with a larger stepper (>1.5A) in a hotter environment to see when the TMC shuts down. I am considering a different fab that allows thicker copper layers for better heat spead, and better power margins. * The CAN bus works good after some software work. It should work fine with up to 8 nodes on each bus, possibly more. I have run 4 boards on the same bus, each with one stepper, simulating a complete 3D printer. @@ -54,6 +48,15 @@ It is possible to fit different connectors for most functions. It is designed fo For a larger (>30) production run the boards would have to be panellized, which looks like a non-trivial task with KiCAD. If anyone has experience and wants to help ... -![Can Hat](CanHat.jpg) -As a sub project to this board I have developed a little power and CAN distribution board combined with an STM2515 CAN bus controller in the form of a Raspberry Pi Hat. It is a very simple little board but has turned out to be very valuable. With some more thought put into it I think it will be a good complement to the Huvud tool board. It has to be modified to allow it to be used separate from a Pi with a different CAN controller. It also needs some fuses, a proper isolated CAN tranciever, more flexibility for the CAN termination and connectivity. A an option to fit a voltage regulator to power the Pi from the boards power. And mosfets to power down the boards ... feature creep... +2020-06-04: + +Version 0.4 in the works... + + +# Can Hat +![Can Hat](CanHat.jpg) + +As a sub project to this board I have developed a little power and CAN distribution board combined with an MCP2515 CAN bus controller in the form of a Raspberry Pi Hat. It is a very simple little board but has turned out to be very valuable. + +With some more thought put into it I think it will be a good complement to the Huvud tool board. diff --git a/doc/Huvud0.4Render.jpg b/doc/Huvud0.4Render.jpg index 6159f02..791a279 100644 Binary files a/doc/Huvud0.4Render.jpg and b/doc/Huvud0.4Render.jpg differ diff --git a/doc/printer.cfg b/doc/printer.cfg index 8485749..67c8a17 100644 --- a/doc/printer.cfg +++ b/doc/printer.cfg @@ -5,7 +5,7 @@ [mcu head0] serial: /tmp/ttyCAN3 - +restart_method = command [extruder] step_pin: head0:PB3 @@ -39,3 +39,5 @@ heater_temp: 50.0 [fan] pin: head0:PA7 # "FAN0" + +# endstop_pin = head0:PA1 "ENDSTOP", active low