overview.rst
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We update the documentaiton and CI tooling to remove references to the jailbreak firmware. We also slightly update the docs to mention USB mode in a separate page, for unification purposes.
We update the documentaiton and CI tooling to remove references to the jailbreak firmware. We also slightly update the docs to mention USB mode in a separate page, for unification purposes.
Overview
To make the most of card10's dual-core processor, its firmware will have been divided into two parts: The "main" firmware running on core 0 which will have been called Epicardium and the "user-code" running on core 1. In most cases this will have been Pycardium, our MicroPython port.
Epicardium
Epicardium is based on FreeRTOS. There are a number of tasks that will have been keeping card10 running. These are:
| Name | ID Global | Priority | Description |
|---|---|---|---|
| vPmicTask |
pmic_task_id (static) |
+4 | Power Management (and Reset Button) |
| vLifecycleTask |
lifecycle_task (static) |
+3 | Control of the payload running on core 1. |
| vBleTask |
ble_task_id (static) |
+3 | Bluetooth Low Energy Stack |
| vSerialTask | serial_task_id |
+3 | Serial Output via UART/CDC-ACM/BLE |
| vApiDispatcher | dispatcher_task_id |
+2 | Epicardium API dispatcher |
| vLedTask | -/- | +1 | LED Animations |
| vMAX30001Task |
max30001_task_id (static) |
+1 | MAX30001 ECG driver |
| vBhi160Task |
bhi160_task_id (static) |
+1 | BHI160 sensor fusion driver |
Epicardium API
Epicardium exposes lots of functionality via the Epicardium API. The technical details of this API can be found in this :ref:`overview <epicardium_api_overview>`. If you are interested in adding new API calls, you should probably read the :ref:`epicardium_api_guide` guide.
Pycardium
Pycardium is our MicroPython fork. Its purpose is to make it as easy as possible to interact with card10. If you are interested in working on Pycardium, take a look at the :ref:`pycardium_guide` guide.
l0dables
Next to Pycardium, other bare-metal code can also run on core 1. For example, a Rustcardium or C-cardium. These l0dables must be compiled using our special linker script and should link against the api-caller library so they can interface with the :ref:`epicardium_api`.
Note: this feature is disabled by default and has to be enabled in :ref:`card10_cfg`. A :ref:`card10_cfg` file dropped into the :ref:`usb_file_transfer` of the badge containing execute_elf = true is enough.
l0dables are currently built within the source tree of the main repository. See l0dables/blinky for an example of a hello-world-like program. Within those programs, you can access the :ref:`epicardium_api` to control the hardware and behaviour of the badge.
Once you have a built ELF file, you can drop it into the FAT filesystem of the flash (eg. via :ref:`usb_file_transfer`) and it will be available from the menu program of the badge.
Program Flow Diagram
The following diagram is a rough overview of the program flow in this fimware:
