AltSql Realtime Live Demo

A controller runs a loop 100 times a second. Every cycle it writes one value, its state or, every tenth cycle, one of its settings, and logs a row, and those writes must be done within 10 ms of the cycle’s start. Its flash chip needs 45 ms to erase a sector, and up to 400 ms. AltSql Core erases inside the write that needs the room. AltSql Realtime never erases inside a write, and works out from its configuration the most any write can cost. It erases only when the loop calls idle: here, between cycles, while the chip erases in the background.

Simulated chips, real engines. Both engines run in this page, compiled to WebAssembly, each on its own chip. The chips are emulated in memory, and every operation takes the time the chip’s datasheet gives it: typical, or the slowest it allows.

How to Run It

1. Ten seconds. The loop at the chip’s typical timings: where each engine’s writes end, against the deadline.
2. The chip at its slowest. Every program and every erase takes the longest the datasheet allows, for ten seconds.
3. Pull the plug. The power goes on both chips, each at a random byte of its next flash work, and comes back.
4. Stop the erasing. The loop stops calling idle for twenty seconds, then starts again.

On a wide screen the demo has more room: open it full screen.

About AltSql Realtime

AltSql Realtime is storage for a control loop: every write has a limit on its flash work, worked out from the configuration before the device runs, and no write ever erases. The one call that erases runs when the application has time for it, with a flash driver that lets the chip erase in the background; the demo models such a driver. On a model of a common flash chip, with times computed from its datasheet, ten seconds of a loop writing every 10 ms missed none of their 1,000 deadlines, while the same loop on AltSql Core missed 76 at the chip’s typical timings and 829 at its slowest.

AltSql Realtime is a prototype, all rights reserved. It works and is tested in simulation on a PC, with times on a chip computed from its datasheet, and it has not yet run on a microcontroller: that is the Beta. Its Alpha report sets out how it was built and tested, and how each figure was measured or computed. Device makers and investors can ask for it through the contact page.

More: all live demos and the engines.