50 lines
1.4 KiB
Markdown
50 lines
1.4 KiB
Markdown
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# Fomu FPGA Tools
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The EVT version of Fomu is a "stretch" PCB with a Raspberry Pi header. Additionally, the factory test jig for production versions of Fomu has pins that match up with a test jig with the same pinout.
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These tools can be used to control an FPGA and its accompanying SPI flash chip.
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## Building
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To build this repository, simply run `make`.
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## Loading a Bitstream
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The most basic usecase is to load a program into configuration RAM. This is a very quick process, and can be used for rapid prototyping.
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To load `top.bin`, use the `-f` argument:
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```sh
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# ./fomu-flash -f top.bin
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```
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This will reset the FPGA, reset the SPI flash, load the bitstream into the FPGA, and then start running the program.
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## Programming SPI Flash
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To write a binary file to SPI flash, use `-w`:
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```sh
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# ./fomu-flash -w top.bin # Write top.bin to SPI Flash
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# ./fomu-flash -r # Reset the FPGA
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```
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This will erase just enough of the SPI to hold the new binary file, then flash the binary to SPI.
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It will not reset the FPGA. To do that, you must re-run with `-r`.
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## Verifying SPI flash
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You can verify the SPI flash was programmered with the `-v` command:
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```sh
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# ./tomu-flash -v top.bin
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```
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## Checking SPI Flash was Written
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You can "peek" at 256 bytes of SPI with `-p [offset]`. This can be used to quickly verify that something was written.
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numbers seen in https://elinux.org/File:Pi-GPIO-header.png
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