ClusterHAT - FAQ
Q1: What does the ClusterHAT come with and what do I need to use it?
Q2: Can the ClusterHAT be used with a Raspberry Pi 2 (v1.2) or 3?
Q3: How do I use the console connector?
Q4: What are the solder bridge/jumpers for?
Q5: Which Raspberry Pi models can I use for the controller?
Q6: Do I need an SD card for each Raspberry Pi Zero?
Q7: Why do you only use one micro USB connector on the Pi Zero?
Q8: Can I use a Camera on a Pi Zero 1.3?
Q9: What PSU do you recommend?
A1: The ClusterHAT is supplied with 4*12mm M2.5 spacers and 8*6mm M2.5 screws to secure the ClusterHAT to your Raspberry Pi. You will need to supply your own USB cable (at least 20cm) and stick on feet (to prevent the screws from scratching the table surface) should they be required. You will also obviously need to provide your own controlling Pi (A+/B+/2/3), 1 to 4 Pi Zeros and associated micro SD cards/etc.
A2: The ClusterHAT can be used with a Raspberry Pi 2 (v1.2) and 3 but please be aware the Pi may get HOT when covered by the HAT causing the CPU speed to be reduced (towards 600Mhz). The Raspberry Pi 2 (v1.1) is less likely to reach temperatures high enough to throttle the CPU frequency.
A3: The serial console connector is designed for use with the Sparkfun FTDI Basic 3.3V or Sparkfun Beefy 3. The 5V version MUST NOT be used since the Raspberry Pi GPIO are only 3.3V tolerant.
A4: Upto v1.1 the "W EN" jumper (close to the GPIO connector) when bridged allows the HAT EEPROM to be modified. The 2 way PWR solder bridge is used to select the power source for the Pi Zeros. Bridging "USB" to the centre pad will source power from the female Micro USB connector, bridging "RPi" to the centre pad (the default) will source power via the 5V GPIO header (you must bridge only one option).
A5: You can use any Raspberry Pi model with a 40 pin GPIO header to control the ClusterHAT - A+/B+/2/3 or even another Raspberry Pi Zero although it's not very practical.
A6: Currently an SD card is needed for every Pi Zero.
A7: The "USB" connector can be used for both power and data (the "PWR" connector is power only). The "USB" and "PWR" connectors are connected together via a 0R resistor on the Zero. There is also no power protection circuitry on the Pi Zero so powering via GPIO, USB or PWR connectors is effectively the same.
A8: Yes, you will need to enable the camera as normal using "sudo raspi-config".
A9: For the Pi(1) and old model Pi2 (with BCM2836) we recommend using a 2A PSU and for the newer Pi2 (BCM2837) and Pi3 a 2.4A PSU.
We have also started a collection of How To for the Cluster HAT.