Build Notes
General notes on things to look for when building the board: [Board-Layout-Overview.pdf](https://github.com/futurexdesign/KiwiBoard/files/11278860/Board-Layout-Overview.pdf
No matter what 5160 board is used, it will need to be configured into the correct mode for use in the KiwiBoard. We need the SPI Mode enabled, so that we can communicate with the board. We also need SD (Step/Direction) mode DISABLED so that the internal ramp generator controls the movement.
The single most common use of these stepper boards is in 3D printers. In that application, they set them to SPI_MODE=1 and SD_MODE=1, as they use their internal firmware to control all movement, and only use the SPI connection to configure the drive parameters.
Setup Required SPI_MODE = 1 SD_MODE = 0
This is the Official Trinamic Version of the StepStick. Ensure that the unit must be the TMC5160 version, as the built in motion controller is required.
**- The TMC5160 SilentStepStick requires that you cut the SD jumper to Disable SD mode, and only have SPI mode enabled. **
- This trace is on the BOTTOM of the board. ONLY cut the SD trace on the left side. Do not cut the SPI jumper trace. You just need to make sure the 2 SD pads are no longer shorted together by the trace. Use care not to cut too deep, it is a 4 layer board.
- Pinout: https://learn.watterott.com/silentstepstick/pinconfig/tmc5160/
- The Trinamic board comes with no heatsink. Under test usage, I've not yet see it get warm. The IC does have overtemp protection built in, and will shut itself off if the temp gets too high. The firmware will be adjusted to look for this error and intercept it should it occur. Many of the aftermarket versions of the board come with heatsinks, they shouldn't affect anything, and can never hurt.
Main micro-controller is a RaspberryPi Pico. The board has a footprint which can accept the micro-controller in either a surface mount, or pin header configuration, depending on your taste.
- Pico W should work, but as of now, not tested. There is no keep-out area made for the antenna, so reception my not be ideal.
Main power connector footprint is on a 5mm pitch. High end option for connectors would be Phoenix LPT tool-less connectors. If you can source them, they are very nice to work with. SPT would be an option as well for a screw terminal version of the connector, which may be less expensive. These connectors do not require a harness connector, they accept the bare wire.
The LCDand Encoder connectors are JST PH series connectors. You can usually find these in pre-terminated pig-tail harnesses, or in a kit that includes pre-terminated wires and the connector body. These should be easy to find anywhere in the world. A 5 pin and 9 connector are needed.
The expansion header is spaced for normal ..1" pin headers/socket ("Dupont Connectors"). In a normal build, this is left unpopulated.
- If using single row terminal blocks, these will not fill the entire footprint. It is recommended that you mount the connector such that the part is mounted closest to the rest of the circuit it is connected to (So inboard in pretty much every case). It is also worth it to fill the empty holes with solder to increase current capacity across the pad.
- If you have the ability to use a power supply that has a current limiter, it is recommended you use it for the first power up. While the board does have a protective 10A PolyFuse installed, it is more similar to a slow-blow fuse than a circuit breaker. It isn't wise to count on it for powering up a new build if you can avoid it.
- If the PolyFuse does open, it will self-reset, but this may take quite awhile, as it is temperature based. the internals of the polyfuse need to cool down in order to allow current to flow again.
- It is recommended that the passive components and voltage regulator are installed first. Power up the board with just these components installed and verify the 3.3V power rail is working as expected. This can be easily found at pin 2 of the expansion header, or on the OLED and Encoder headers.
- Double check the orientation of the voltage regulator module. Pin 1 is oriented towards the main 12V power input. If you get it backwards, it will be destroyed in dramatic fashion 🔥
- Once power rail is verified, the semiconductor parts can be installed.
- Ensure that the stepper module is in SPI mode before installation.
- Use extra caution when soldering transistor Q1, the pin pitch is very tight for a through-hole part, and it is easy to short two pins. Verify there is no short before powering on the board!
- It is recommended that the Pico be flashed before installation on the board.
- The Pico and Stepper board can be socketed if desired by using common .1in pin sockets. This is not required, and for the stepper board, may not be recommended due to the motor current.
J5 - LCD 9 Pin JST PH connector. Pinout in order of the pinout on the LCD module. Verify connection is oriented correctly on the LCD side, as it is not keyed. Connecting backwards may cause permanent damage to the LCD module.
Pin 1 is to the RIGHT edge of the board.
| Pin | Purpose |
|---|---|
| 1 | 3.3v |
| 2 | Ground |
| 3 | LCD-CS |
| 4 | LCD-RESET |
| 5 | LCD-DC |
| 6 | LCD-MOSI |
| 7 | LCD-SCK |
| 8 | LCD-Backlight |
| 9 | LCD-MISO |
**Pin 1 is to the RIGHT edge of the board (Viewed from top). ** Mount connector on back side of board Ground pin is closes to the near edge of the board. This is being mounted on the back to make the installation easier.
| Pin | Purpose |
|---|---|
| 1 | Ground |
| 2 | 3.3V |
| 3 | Encoder Button |
| 4 | Encoder Output 1 |
| 5 | Encoder Output 2 |
Pin 1 is to the left, closest to left board edge.
| Pin | Purpose |
|---|---|
| 1 | Ground |
| 2 | 3.3V |
| 3 | GPIO 0 (SPI0 MISO) |
| 4 | GPIO 1 (SPI0 CS) |
| 5 | GPIO 2 (SPI0 CLK) (I2C1 SDA) |
| 6 | GPIO 3 (SPI MOSI) (I2C1 SCL) |
The Wiring of the KiwiBoard is much simplified when compared to the stock KiwiCleaner build. The KiwiBoard becomes the hub of the machine, and connects directly to all of the other components with "home-run" wiring. This eliminates the various junction points in the original wiring harness.
- Main input power is 12V up to 10A. Ensure correct polarity, the board does NOT have any reverse polarity protection.
- The board contains a 10A self-resetting PolyFuse for protection in case of gross overloading. If this trips, the fuse will need to cool off to reset.
- The main 12V input line can be switched if the user desires. The board itself has no power-saving mode, or soft power-off functionality, so it should be powered off when not in use.
- Motor Connections
- The motor connections should be oriented in the same order as they were connected to the original KiwiCleaner motor controller. If the motor does not want to run smoothly, check that the A and B motor phases are connected correctly, and reverse any pairs that may not be correct.
- Keep these wires are short as reasonably possible, and of sufficient gauge. The motor can draw up to 3A when accelerating and decelerating though low speeds in a wash cycle.
- Heater Connection
- Heater element should be connected directly to the KiwiBoard, with no additional switches.
- Polarity should be observed when connecting to the board.
- Wires should be sufficiently sized for up to 8A of current at a minimum.
- Fan Connection
- Fan should be connected directly to the KiwiBoard, and not tied into the heater connections in any way.
- The KiwiBoard expects to have full control over the fan.
- This is a low current connection, the wiring can be sized accordingly.