#Chaos Control Board

This will be a control board for 3D printers using 32 bit and the TMC2130 stpper driver.

features

• 32 bit
• TMC2130 stepper driver
• Marlin firmware
• Teensy 3.6 based
• 12V - at least 24V (the limiting factors are stepper driver, hotend, heatbed)
• SPI for the stepper driver is routed directly on the board
• enable and direction over SPI (needs Marlin patch)
• steps over SPI?
• sensorless homing, no x/y endstops needed. diag1 of the TMC2130 will be directly routed to the endstop pins of the controller
• Raspberry Pi Zero W connected to a pin header on the board with power and rx/tx
• step down for 5V and 12V
• 3 pwm controlled fans, each fan can be jumpered to use vcc, 12V or 5V
• if possible THT design to make it easier to build one
• JST connectors
• 2 connectors for Z to drive two motors with the same driver
• onboard optocoupler for Z probe
• BL Touch support
• 5 stepper driver onboard, expansion header to support more

open points

• heatbed mosfet onboard or only control connector to an external mosfet?

possible future features

• ws2812 controlled LEDs (does Marlin supports this?)
• flash firmware using the Raspberry and Octoprint (needs modified bootloader on the Teensy to use rx1/tx1 instead of rx0/tx0 from the default usb connector)
• filament sensor using the sensor from an old optical mouse (does Marlin already supports this?)

Teensy pinout planning

• 42 GPIO on the default pin headers (we should use them for all default features if possible)
• 20 more GPIO are accessible with smd pin header

needed pins

SPI

• SDO
• SCK
• SDI

stepper driver

• X CS
• X Step
• Y CS
• Y Step
• Z CS
• Z Step
• E0 CS
• E0 Step
• E1 CS
• E1 Step

thermistor

• bed
• hotend 0
• hotend 1

fans

• part cooler
• fan 2
• fan 3

display

• 9?
• sd?

misc

• heatbed
• rpi tx
• rpi rx