I’m Tomu FPGA (Fomu for short!) a tiny FPGA board which fits in your USB port. People sometimes call me "Fomu" for short!
I have two buttons and an RBG LED.
Professionally produced Tomu boards have the following color scheme; * Tomu FPGA boards are blue. * Original Tomu boards are green.
However, as people are encouraged to produce their own Tomu boards, please look at the device careful to check what type you have. See the following table for what to look for;
Original Tomu |
Tomu FPGA |
|
Board Color |
Green |
Blue |
LEDs |
One Green + One Red |
One Red Green Blue LED |
Components |
A single large black IC taking up most of the board. |
Multiple little black ICs covering the board. |
Test point pattern |
FIXME |
FIXME |
The original Tomu has one large black IC on the board.
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Announcement mailing list - Low traffic list for announcements.
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Discussion mailing list - List for discussing development / new features / etc.
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IRC Channel - irc://irc.freenode.net/#tomu - IRC channel for discussing anything related to the project.
There are currently two versions of Tomu FPGA. Both boards and based around mostly the same schematic and should be mostly compatible and based around the Lattice iCE40UP5K FPGA and have the same set of features listed below;
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5K 4 input LUTs + DSP tiles
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128 kilobytes internal SRAM
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1024 kilobytes (or more) flash (XIP possible)
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1 x RGB LED
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2 x touch buttons
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The hacker version is designed for people who are up to the challenge of building their own board.
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It has a simpler PCB which makes it cheaper to produce in a small quantities.
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However, it uses a non-standard footprint for the FPGA WSCP which reduces yield and long term reliability making it unsuitable for mass production.
Caution
|
This PCB specification is currently a work-in-progress. |
Board Size |
0.37 x 0.51 inches (9.5 x 13.1mm) |
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Board thickness |
0.6mm |
Number of Layers |
2 |
Components |
Single Side |
Silkscreen |
None, one side or all sides is fine. |
Number of through holes |
0 |
Minimum trace width and clearance |
4mil traces, 4mil clearance |
Vias + Drills |
0.2mm via drills with 0.5mm annular rings |
Smallest pitch size |
0201 resistors, WCSP parts |
Control Impedance |
Not required |
Solder Mask color |
Blue |
Plating |
ENIG |
Material |
FR4 |
V |
Vcc |
0.000 x 0.275 in |
S |
SPI_CS |
0.000 x 0.160 in |
C |
SPI_CLK |
0.000 x 0.0825 in |
I |
SPI_MISO |
0.027 x 0.000 in |
O |
SPI_MOSI |
0.100 x 0.000 in |
R |
RESET |
0.170 x 0.000 in |
G |
GND |
0.302 x 0.0000 in |
Laser cut SVG for the programming jig for use with fomu-flash tools. The pinout works for both the Pi 2 and Pi 3.
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The production version is designed for mass production.
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It uses advanced PCB technologies like laser drilled and blind vias.
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You get a production version if you order from Sean \'xobs' Cross through or after the Crowd Supply campaign.
Caution
|
This PCB specification is currently a work-in-progress. |
Board Size |
0.37 x 0.51 inches (9.5 x 13.1mm) |
---|---|
Board thickness |
0.6mm |
Number of Layers |
4 |
Components |
Single Side |
Silkscreen |
Both |
Number of through holes |
0 |
Minimum trace width and clearance |
0.1mm track width, minimum clearance is 0.1mm |
Vias + Drills |
|
Smallest pitch size |
0201 resistors, WCSP parts |
Control Impedance |
Not required |
Solder Mask color |
Not-green |
Plating |
|
Material |
FR4 |
Supported by the LiteX BuildEnv. The LiteX BuildEnv supports your choice of CPU architecture;
As the board is supported by the LiteX BuildEnv, you can developed;
The contents of this repository excluding
third_party
folder is released under your choice
of the following two licences:
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the "Creative Commons Attribution-ShareAlike 4.0 International License" (CC BY-SA 4.0) full text of this license is included in the LICENSE file and a copy can also be found at http://creativecommons.org/licenses/by-sa/4.0/
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the "TAPR Open Hardware License" full text of this license is included in the LICENSE.TAPR file and a copy can also be found at http://www.tapr.org/OHL