Hello all,
I've been working on a 3D printing shield for Teensy 3.5/3.6.
Since I wanted to cram more features on the pcb I decided to use 3x pcf8574 (i2c) for STEP/DIR/EN and CS (for spi drivers).
I've been looking at the teensy 3.5/3.6 pinout file and I don't think it's going to be that easy.
I attached part of the schematic.
How should I go about it?
I really hope I didn't mess this up by making the board before making sure I can define pins over gpio expanders.
I tested all hardware and it works electrically.
There's 6 motor driver sockets, 6 endstops, 3 thermistors (agnd/avcc), one z-probe, one MAX31865 chip for pt100/1000 (with jumper pads for 2-4 wires), 6 fan pwm outputs with option to use 12V for 3 of them, one 12V always on fan, one 24V always on fan, 2 servo connectors (driven by buffer), 3 power supplies that can be replaced (those 1$ buck converters, slim, 4 pins in a row type) 5V, 3.3V and whatever voltage for the 3 fans (all 3 have status led and 3.3V and 12V can be enabled/disabled by teensy, 5V is always on). If they pop they can be replaced by plugging them out of their socket. 2 extruder mosfets and 1 heatbed mosfet that are driven by a buffer. There's 5 fuses (not installed yet), one for each power supply, one for the drivers (24V) and one for bed/extruders.
Drivers can be drv8825/a4988 or spi like tmc2130 or uart like tmc 2208. There's also a sd-card that should theoretically fit the slot on an ender 3. Added also a socket for esp12e format of esp8266 that also can read the sd-card. esp12e has 6 pins broken out, standard lcd/sdcard expansion connectors and I managed to save only two pins, that I chose to be A10/A11 combo for a differential pair setup with a simple input filter.
It would be a real shame if I'm this stupid.
*edit
To be honest now I'd drop a driver space for a relay for bed/extruders so I can have that extra bit of safety. Ender 3 has 9A for the bed and another 2 for the extruder. A 20A could do even with a second extruder. Also got the rotation wrong on power connectors. And there's a precision reference as well for aref.
I've been working on a 3D printing shield for Teensy 3.5/3.6.
Since I wanted to cram more features on the pcb I decided to use 3x pcf8574 (i2c) for STEP/DIR/EN and CS (for spi drivers).
I've been looking at the teensy 3.5/3.6 pinout file and I don't think it's going to be that easy.
I attached part of the schematic.
How should I go about it?
I really hope I didn't mess this up by making the board before making sure I can define pins over gpio expanders.
I tested all hardware and it works electrically.
There's 6 motor driver sockets, 6 endstops, 3 thermistors (agnd/avcc), one z-probe, one MAX31865 chip for pt100/1000 (with jumper pads for 2-4 wires), 6 fan pwm outputs with option to use 12V for 3 of them, one 12V always on fan, one 24V always on fan, 2 servo connectors (driven by buffer), 3 power supplies that can be replaced (those 1$ buck converters, slim, 4 pins in a row type) 5V, 3.3V and whatever voltage for the 3 fans (all 3 have status led and 3.3V and 12V can be enabled/disabled by teensy, 5V is always on). If they pop they can be replaced by plugging them out of their socket. 2 extruder mosfets and 1 heatbed mosfet that are driven by a buffer. There's 5 fuses (not installed yet), one for each power supply, one for the drivers (24V) and one for bed/extruders.
Drivers can be drv8825/a4988 or spi like tmc2130 or uart like tmc 2208. There's also a sd-card that should theoretically fit the slot on an ender 3. Added also a socket for esp12e format of esp8266 that also can read the sd-card. esp12e has 6 pins broken out, standard lcd/sdcard expansion connectors and I managed to save only two pins, that I chose to be A10/A11 combo for a differential pair setup with a simple input filter.
It would be a real shame if I'm this stupid.
*edit
To be honest now I'd drop a driver space for a relay for bed/extruders so I can have that extra bit of safety. Ender 3 has 9A for the bed and another 2 for the extruder. A 20A could do even with a second extruder. Also got the rotation wrong on power connectors. And there's a precision reference as well for aref.
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