PoliTo-ASAC-Lab/ASAC_CPM

ASC_CPM is a Cluster Power Manager solution, to be used for testing purposes or extensive fault injection campaigns involving a cluster of devices. (Daniele Rizzieri - 2023)

ASAC_CPM - ASAC Cluster Power Manager

ASAC_CPM is a Cluster Power Manager solution, to be used for testing purposes or extensive fault injection campaigns involving a cluster of devices. It can be easily adapted to be used with other kinds of board composing the cluster, like Arduino, Raspberry-Pi, others.

HW Setup

The overall setup requires low-cost components only and can be easily adapted and scaled based on necessity. To manage the power supply of the cluster nodes (ON/OFF) a set of relay switches is controlled by a NodeMCU Lua Lolin V3 Module, implementing a user interface accessible through USB-serial connection. Here below is the general scheme of the hardware setup:

Here below the details about the NodeMCU module pin usage:

Note: an additional VCC >= 5V is needed to power the relay switches (!= Relay Ctrl). As can be seen in the HW Setup general scheme, the PS line could be used for this purpose.

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Here below a photo of an ASAC_CPM istance, as it has been mounted in ASAC Laboratory @ DAUIN, Politecnico di Torino:

Note: in this model/setup, 8x TUL PYNQ-Z2 MPSoC Development boards have been used to compose the cluster. To edit each FTDI device serial name, and thus be able to manage all the boards singularly, refer to ftdi-serial-flasher repository, by @EdwarDu.

Getting Started

To initialize the CPM, MicroPython firmware has to be flashed on the NodeMCU module, together with some source code implementing the control interface.

0. Install CH340 Driver: from this link.

1. Installing MicroPython firmware: follow this guide docs/ESP8266_uPy_guide.pdf.

2. Uploading the uPy source files enabling control interface

   2.1) Install adafruit-ampy on your local machine, to upload/update source files stored in the ESP8266's flash memory.

   pip install adafruit-ampy

   2.2) ampy can now be used to upload, download, list files and create directories inside the on-board flash memory. To upload the source files for the control interface (find them in /NodeMCUv3_uPy_src folder), execute the following commands in a terminal:

   PORT="/dev/ttyUSB0"
   ampy -p $PORT put main.py
   ampy -p $PORT put boot.py
   ampy -p $PORT mkdir lib
   ampy -p $PORT put lib/cmd.mpy
   ampy -p $PORT ls

3. Use the control interface

   Once all is set up, you can use the CPM control interface by opening a serial connection (115200-8N1) with the NodeMCU module. If everything is good, a prompt '#' should appear. Here below are the available commands.

   Command	Description
   s	Returns the current ON/OFF state of the cluster nodes.
   y ([1-8] | all)	Power ON the device [1-8] or all the devices.
   k ([1-8] | all)	Power OFF the device [1-8] or all the devices.
   r ([1-8] | all)	Power-cycle (OFF - 1sec - ON) the device [1-8] or all the devices.

Market COTS Alternatives

Here below are some Commercial-Off-The-Shelf alternatives/similar products available on the market (in July 2023):

• Crowd Supply Programmable USB Hubs (202.50$)
• Microchip EVB-USB5734 (536.20€)
• Cluster Triple for Raspberry Pi Compute Modules (49.00$)

The total implementation cost (in July 2023) of the ASAC_CPM is around 20€ (~12.50€ for the 8x Relay Module + ~7.50€ for the NodeMCU V3 Module).