P2-HOST-FS

HOST FS - code for accessing the host filesystem via the 9P protocol

Host Filesystem Features

Key features of this filesystem for the P2 chip:

• Read and write files and directories directly on the host PC
• Transport agnostic; defaults to using the serial port, but can easily be modified to use ethernet or other connections
• Uses the 9P protocol, which is a widely used and simple protocol for network file systems

API

The API for the host file system is very straightforward, and heavily inspired by Stephen Moraco's and Chip Gracey's Parallax Flash File system

Adding the Host FS to your own project

This section describes how to quickly get the host filesystem working in your project.

Include the Host FS object in your top file

Place the downloaded hostfs.spin2 in your project and in your top-level object include the flash object:

OBJ { Objects Used by this Object }

    host  : "hostfs"               ' the host filesystem

Provide a Serial (or other) Interface for the File System

Hostfs needs to talk to the host by some mechanism. The actual interface is very simple: it needs to be able to send a block of data and receive another block as response. The API for this is:

pub sendrecv(bufstart, bufend, maxlen) : reply_len

where bufstart is a pointer to the start of the data to send (and is also where the received data will be placed), bufend is a pointer to the end of the data to send, and maxlen is the maximum size of the buffer. The function returns the actual number of bytes received in the reply from the host.

See the detailed documentation in the .zip file for more details.