jState - Javascript Simulator Extension Interface

The Crossware Cortex-M3 and Cortex-M4 simulators can now be extended using state-of-the-art Javascript.

Google's V8 Javascript engine has been integrated into the Crossware environment to provide this advanced feature and so you can write state-of-the-art Javascript that will be just-in-time compiled to high performance native code.

Using Javascript you can:

• Read and write all CPU core registers
• Read all readable registers of the on-chip peripherals and the NVIC
• Write to all writeable registers of the on-chip peripherals and the NVIC
• Output text to a console view
• Add event handler functions for core simulation events such as beforestep, afterstep, beforego
• Create interval timers and timeout timers that will trigger events on machine cycle count
• Add event handler functions for events of the simulating on-chip peripherals*
• Issue simulation control commands including halt, go, trace, stepinto, stepover, stepout, restart, undo instruction execution, undo command, capture state, clear trip counter, view source code and view disassembly code.

When core, interval and timer events are triggered, the event object passed as a parameter to an event handler contains not only the data (if appropriate) and the event type, but also the elapsed machine cycles and other cycle counter values.

Using these features you can create extensions that range from the extremely simple to the advanced and complex.

Javascript Code Creation Wizards will generate code to read and write core and on-chip peripheral registers, code to issue commands to the simulator and outline event listener handlers, together with the appropriate addListener functions. So implementing simple simulator extensions is fast and easy - it is not necessary to refer to any documentation, the available registers, commands and events are listed and can selectable with a mouse click. On the other hand, complex simulator extensions are possible using the ECMAScript 5 features of the V8 engine.

The Javascript enhancements are included in the Development Suite for ARM Comunity Edition: Try Now.

Sytem requirements: Windows 7 and above.

*Separate documentation will describe the events generated by particular on-chip peripherals.