SPRUJG0B December   2024  – November 2025 F29H850TU , F29H859TU-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Performance Optimization
    1. 2.1 Compiler Settings
      1. 2.1.1 Enabling Debug and Source Inter-Listing
      2. 2.1.2 Optimization Control
      3. 2.1.3 Floating-Point Math
      4. 2.1.4 Fixed-Point Division
      5. 2.1.5 Single vs Double Precision Floating-Point
      6. 2.1.6 Link-Time Optimization (LTO)
    2. 2.2 Memory Settings
      1. 2.2.1 Executing Code From RAM
      2. 2.2.2 Executing Code From Flash
      3. 2.2.3 Data Placement
    3. 2.3 Code Construction and Configuration
      1. 2.3.1 Inlining
      2. 2.3.2 Intrinsics
      3. 2.3.3 Volatile Variables
      4. 2.3.4 Function Arguments
      5. 2.3.5 Enabling Wider Data Accesses
      6. 2.3.6 Auto Code-Generation Tools
      7. 2.3.7 Accurately Profiling Code
    4. 2.4 Application Code Optimization
      1. 2.4.1 Optimized SDK Libraries
      2. 2.4.2 Optimizing Code-Size With Libraries
      3. 2.4.3 C29 Special Instructions
      4. 2.4.4 C29 Parallelism
      5. 2.4.5 32-Bit Variables and Writes Preferred
      6. 2.4.6 Coding Style and Impact on Performance
  6. 3References
  7. 4Revision History

2.2.2 Executing Code From Flash

To understand the number of required Flash wait states depending on the CPU clock frequency, see the Flash Parameters section of the F29H85x and F29P58x Real-Time Microcontrollers Data Sheet. Also, make sure Pre-fetch, Pre-read and caches are enabled. Flash_initModule() can be used to perform these operations:

voidFlash_initModule(uint16_twaitstates)
{
   ..
   // Set waitstates according to frequency
   Flash_setWaitstates(waitstates);
   ..
   // Enable data cache, code cache, prefetch, and data preread to    improve performance of code// executed from flash.
   Flash_configFRI(FLASH_FRI1, FLASH_DATAPREREAD_ENABLE | FLASH_CODECACHE_ENABLE | FLASH_DATACACHE_ENABLE | FLASH_PREFETCH_ENABLE);
   ..
}