zappem.net/pub/io/iovm

iovm - a package for algorithmically setting IO signals.

Overview

The package iovm is inspired by the x/net/bpf package. However, this present VM operates on signal bit IO banks and int64 numerical vectors with a more restrictive instruction set that include both reading and writing those values.

Automated package documentation for this Go package should be available from .

Status

This project is intended to use such an execution model to build logic systems with something approximating realtime behavior. Since Go does not guarantee realtime execution, we can only measure how reliable the timing appears to be and offer this visibility as an easy to determine metric for performance.

The current status of the project is that we can execute sequences of iovm.Code and permit instruction tracing. The code includes one primitave for concurrency management: the JumpOrRaise() operation.

The only examples of code at present are in the iovm_test.go file.

TODOs

• Run a sequence with GPIOs once every 100ms on an RPi and measure its completion latency.
• Use the iotracer and gpio packages to export its wave trace as a VCD file.

In the distant future, we might consider compilation to binary form for running on actual realtime devices. However, right now we are focused on interpreted timing on Linux devices.

License info

The iovm package is distributed with the same BSD 3-clause license as that used by golang itself.

Reporting bugs and feature requests

The package iovm has been developed purely out of self-interest and a curiosity for debugging physical IO projects, primarily on the Raspberry Pi. Should you find a bug or want to suggest a feature addition, please use the bug tracker.