tillitis-key/doc/system_description/boards.md
Joachim Strömbergson a15a94fe8e
Move readme:s for boards and firmware to doc subdir
Signed-off-by: Joachim Strömbergson <joachim@assured.se>
2022-11-21 16:27:30 +01:00

2.4 KiB

MTA1-USB PCB designs

Boards

The KiCad board projects all follow this directory structure:

Path Description
/project KiCad 6 project
/project/gerbers PCB release files
/project/test Scripts / gateware used for production tests

mta1-usb-v1

This is the first production version of the MTA1-USB design.

Main features:

  • Miniaturized hardware the size of a small USB stick.
  • The Interface FPGA from the MTA1-USB-DEV design has been replaced with an Interface MCU running a USB-to-Serial converter firmware. This was done to ease development of the FPGA design.
  • A touch sensor IC is provided instead of the switch for user presence detection.
  • Test pads are provided on the bottom of the board for programming the SPI flash, and also for measuring extra GPIO pins. The 'MTA1-USB-V1-Programmer' board is designed to support this.

mta1-usb-v1-programmer

This is a programming jig for the mta1-usb-v1 board.

mta1-usb-dev

This is the original design, intended as a development platform. It is a larger PCB, that connects to a PC via a USB C cable.

Main features:

  • 2 ICE40 FPGAs.
  • The first ICE40 (Interface FPGA) is connected to a USB C plug, and is loaded with a gateware that contains a soft USB device. This gateware acts as an USB-to-GPIO interface to the second ICE40.
  • The second ICE40 (application FPGA) is loaded with a RISC-V soft core containing the security firmware. User applications are run on this gateware.
  • The second ICE40 also has an input button for user presenence detection.
  • An FTDI module is included for programming both the Application and Interface FPGAs.
  • Both ICE40s can be configured to boot from included SPI flash memories, NVCM, or be live programmed from the FTDI module.
  • All GPIO lines between the two FPGAs, as well as all programming signals, are exposed on 0.1" headers for probing.

Libraries

mta1-library

This is a shared KiCad library for all boards in the project.

KiCad-RP Pico

This is a KiCad library for the Raspberry Pi Pico symbol and footprint. It was extracted from the Kicad-RP-Pico project. It is licensed under the Creative Commons CC-BY-SA 4.0 License, with an exception exempting waving any control of derived works.