2 Memory Layout and Requirements

Microchip Thread SDK Memory Layout:

The following image displays the flash and RAM layout of WBZ451, specifically for applications utilizing Microchip Thread SDK.

Figure 2-1. Thread Stack Program Memory Layout
Figure 2-2. Thread Stack Data Memory Layout
Figure 2-3. Thread Boot Rom Layout
Note: It is recommended to adjust the Free RTOS Heap Size (configTOTAL_HEAP_SIZE) to 45k while using bootloader services(Default Free RTOS heap size is 40k).

Memory Requiremnets:

The following table presents the Flash and RAM usage information recorded for different roles and features of the thread SDK. These values were obtained by referring to the configuration specified in the openthread_stack_config.h file and can be customized to meet the specific requirements of the application. The configuration file can be accessed from the Header Files → driver/thread/inc path.

Flash and RAM requirements of thread SDK for system-on-chip(SOC) based designs:

The following memory information is provided as a reference for scenarios with and without the CLI App. The SDK package includes IEEE 802.15.4 PHY Lib, OpenThread, Peripheral Libraries (Plibs), FreeRTOS, and other components. The default allocation for FreeRTOS Heap is 46kb and compiler optimization level is 2.

Table 2-1. 
Device TypeRoleAppIn Band CommissioningTotal Data Memory [KB]Total Program Memory [KB]
Commissioner Joiner
FTDLeader/RouterCLIYesYes94407
MTDEnd DeviceCLINAYes84329
FTDLeader/RouterCLINoNo94392
MTDEnd DeviceCLINANo84325
FTDLeader/RouterNo AppYesYes90326
MTDEnd DeviceNo AppNAYes79262
FTDLeader/RouterNo AppNoNo90316
MTDEnd DeviceNo AppNANo79259

Flash and RAM requirements of thread SDK for radio Co-processor (RCP) based designs:

The SDK package includes IEEE 802.15.4 PHY Lib, Part of open thread to support RCP including spinel, Peripheral Libraries (Plibs), FreeRTOS, and other components. The default allocation for FreeRTOS Heap is 46kb and compiler optimization level is 2.

Table 2-2. 
Device TypeAppTotal Data Memory [KB]Total Program Memory [KB]
Radio Co-Processor(RCP)rcp5991