UART2NAND

Interface for exposing raw NAND i/o over UART to enable pc-side modification.

Code is messy and lacks documentation but currently enables reading, flashing, and page-erasing of raw NAND using UART. See nand_example.py for a set of simple examples of how to interface software-side in a way that can be automated.

Plan to rebase this tool from being a linear state machine Soon(tm).

INTERFACE

To interface with the NAND, set up a UART bridge between your PC and the FPGA, and send commands of the following format:

"[command byte]:[address]:[data]"

Where command byte is one of the following:

• "P" -- Program
• "R" -- Read
• "E" -- Erase

Address is 5 bytes, with the first 3 being row address and the last 2 being column address.

Data is 2112 bytes (2048 data bytes + 64 "spare" bytes)

Each field needs 1 byte between them. This byte will be ignored by the hardware, meaning the developer can use whatever character they choose for separation. I used ":", resulting in a command structure that looked like:

P:iiiii:xxxxxxxx....xxxx (dots fill in space so that there are 2112 x's)

In this example, we write to address 0x6969696969 ("iiiii") (not normally accessible on any SLC flash chip), and write the byte 0x78 2112 times.

NOTE: A command will always result in the hardware spitting back out its command as a way to simplify design. In the case of read operations, the 2112 data bytes will overwrite the 2112 data bytes of the sent command.

See nand_example.py if any of this doesn't make sense.

DISCLAIMER

I make no claims of stability and assume no responsibility for potential damages to devices that may be caused by this code, use at your own risk.

LICENSE

This project assumes an MIT License. If you need to use this in a way that works outside that license, feel free to contact me.