Commit Graph

11 Commits (9218e647e0868ae68608aab18b53c6c417fe5240)

Author SHA1 Message Date
Joe Finney 9218e647e0 microbit: Refactor of periodc timer callbacks
- Factored periodic timer funcitonality out of fiber scheduler and into a new SystemTimer module module.
- Enapsulated "ticks" variable within SystemTimer module, with accessor funciton.
- Added accessor/mutator functions to get and set the tick period.
- Added a class wrapper to permit periodic callbacks to both C and C++
  functions.
- Updated all references in microbit-dal to use this refactored API.
2016-03-10 17:01:17 +00:00
Joe Finney 5231b5f526 First cut at a build without a global MicroBit singleton 2016-03-10 12:02:13 +00:00
Joe Finney d3922d21e9 microbit: Aligning MicroBitButton and MicroBitMultiButton APIs
Updates to MicroBitButton and MicroBitMultiButton to align the API through
which CLICK events are filtered. Also, updates to the mechanism through which
buttonA and buttonB CLICK/LONG_CLICK events are filtered by
MicroBitMultiButotn to reduce RAM footprint.

No changes to external behaviour of these classes.
2016-02-26 15:42:57 +00:00
Joe Finney c1ae235ebd microbit: On demand suppression on button click events.
MicroBitMultiButton now provides an indication to MicroBitButton instances when an application is actively utilising that button as part of a button group. This
permits that MicroBitButton to more accurately filter events, and provide a
consistent abstraction.

More specifically, this patch:

 - Extends the MessageBus functionality to indicate when listeners are
   attached to events. This allows components to perform on demand tailoring
   of their behaviour.

 - Extends MicroBitMultiButton to indicate to relevant MicroBitButton
   instances when they are part of a button group.

 - Extends MicroBitButton to perform filtering of button events dynamically
   (rather than statically) when part of a MultiButton group.

 - Code cleanup of static functions that are more cleanly implemented as
   methods.
2016-02-08 13:31:48 +00:00
James Devine 8d3f3affbd microbit: fix for #73
The destructor for MicroBitButton didn't take into account the fact that
an instance can be destructed after registering a callback. This would then
result in a HardFault if an instance was destructed.

A clear repro case was registering a Touch input on a pin (abstracted as a button)
and swapping to a DigitalIn.
2016-01-13 14:15:50 +00:00
James Devine d2df88417b microbit: whitespace changes to MicroBitButton.h and .cpp
Cleared the files of trailing whitespace, and tabulated lines
2016-01-13 14:07:10 +00:00
Joe Finney 194f19a428 Merge branch 'simplified-eventing' 2015-11-01 18:22:27 +00:00
Joe Finney 84da6a4a09 microbit: Minor bug fixes and refinements
- Add maximum depth for event queues, to prevent buggy scripts causing total memory exhaustion.
  - Suppress generation of A/B click events when A+B click is generated
  - preservation of event ordering on messagebus for resursive event generation cases.
  - bugfix of message bus processing to prevent occasional dual processing of events
  - bugfix MicroBitDisplay to behave correctly when delay parameter is zero.
2015-10-31 10:27:38 +00:00
Joe Finney 823a956d68 microbit: First cut at updates to provide tight validation within the runtime code, with a view to moving
NOP/clamping behaviour out of teh micro:bit runtime and into the glue layers of higher level
languages.

 - Updates to many functions to provide explicut return codes.
 - Updates to many functions to remove heuristic calidation (NOP/clamping/defaults)
 - Updates to ErrorNo.h to provide clearer return values, and place return values in a better scope
 - Updates to MicroBitDisplay to use enums where appropriate.
2015-10-25 21:51:33 +00:00
Joe Finney 857a626ed0 microbit: Memory Optimisation Mega Update
This release contains a widespread set of updates and optimisations to the micro:bit
runtime, with a view to reducing the SRAM footprint of the whole system. This is to
provide as much usable HEAP storage for application programs as possible.

Specific updates and optimisations include:

  - Additional compilation flags to allow the core micro:bit runtime to be configured.
    These are defined in MicroBitConfig.h

  - A custom heap allocator. This is now included for two reasons:

    1) To provide a simple mechanism to to utilise both the mbed heap space and other memory
       regions (such as unused memory in the SoftDevice region) as a single virtual heap.
    2) To address some issues that have been noted that are attributable to heap fragmentation.
       The micro:bit heap allocator has a simple algorithm, but one that is chosen to respond
       well to the relativelt high 'heap churn' found in the micro:bit environment.

    All micro:bit components and user programs now use this heap allocator trasparently.

  - Updates to BLE services to remove persistent references to their GATT services. This consumes
    vast amounts SRAM, rather unecessarily. Instead only handles to the relevant GATT characteristics
    are now stored. This specifically includes:
      + MicroBitDFUService
      + MicroBitEventService
      + DeviceInformationService

  - Updates to the Fiber scheduler to save SRAM. More specifically:
      + Removed the need to hold an empty processor context to intialise fibers.
      + The IDLE fiber now runs without a stack
      + fiber stacks are now only created when a fiber is descheduled for the first time, thereby reducing heap churn.
      + the 'main' fiber is now recycled into the fiber_pool if it leaves app_main()
      + fibers created through invoke() now only maintains the necessary part of teh parent stack that is needed, thereby
        reducing the stack size of spawned fibers.

  - Updates to the Message Bus to reduce the overall memory footprint of processing events. More specifically:
      + Event handlers are now always called using invoke(), such that non-blocking event handlers no longer need
        a dedicated fiber to execute - thereby saving SRAM and processor time.
      + Processing of events from the event queue is now rate paced. Events only continue to be processed as long as there
        are no fibers on the run queue. i.e. event processing is no longer greedy, thereby reducing the number of fibers
        created on the runqueue.

  - Updates to BLUEZOENE code to bring up core BLE services even if they are not enabled by default. This allows
    programs that do not require BLE to operate to benefit from the full range of SRAM, whilst still allowing the
    device to be programmed over BLE.

  - Updates to the Soft Device initialisation configuration, reducing the size of the GATT table held in the top 1.8K
    of its 8K memory region to around 800 bytes. This is sufficient to run the default set of BLE services on the micro:bit
    so the additional memory is configured as HEAP storage by MicroBitHeapAllocator.

  - Minor changes to a range of components to integrate with the above changes.
    + rename of free() to release() in DynamicPWM to avoid namespace collision with MicroBitHeap free()
    + rename of fork_on_block to invoke() to enhance readbility.

  - Many code cleanups and updates to out of date comments.
2015-08-31 23:25:10 +01:00
James Devine 538e1c48bd microbit-dal: Initial Commit
This is the first commit of the microbit-dal on GitHub.
This repository contains the runtime, which is a light
weight operating system developed by Lancaster University.
2015-08-12 11:53:41 +01:00