From da691c23662f7fce27ee981c651ee4e915361131 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mario=20H=C3=BCttel?= Date: Sun, 20 Dec 2020 19:52:16 +0100 Subject: [PATCH] Edit readme --- README.MD | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/README.MD b/README.MD index ff4e457..74c9317 100644 --- a/README.MD +++ b/README.MD @@ -8,9 +8,9 @@ Currently, the template is for the STM32F407VEx controllers which have 512k of F # Structure -- the whole project is built by a sinbgel ``Makefile``. On one hand, this is rather comfortable, but can become quite a pain for larger projects. +- the whole project is built by a single ``Makefile``. This is rather comfortable, but can become quite a pain for larger projects. - The ``obj`` folder contains all build derived files. -- The ``startup`` folder contains my own startup code written in C. Most projects for STM32 controllers use Assembly for their startup codes, which is unnecessary. A downside of the C startup code, is that it has a slighly bigger memory footprint. +- The ``startup`` folder contains my own startup code written in C. Most projects for STM32 controllers use Assembly for their startup codes, which is unnecessary. A downside of the C startup code, is its slighly bigger memory footprint. - The ``stm32f407ve.ld`` is the linkerscript. - The ``setup`` folder contains ST's generated clock setup file. It contains the ``SystemInit()`` function which configures the system clocks and flash waitcycles. It is currently set up for a system frequency of 168 MHz. The Code is automatically called by the startup code right before jumping into the ``main()`` function - The ``mathlib`` folder contains CMSIS's math and DSP library in form of a precompiled static library and the corresponding header file. I never use it. No clue, if it works. A quick function check showed that the functions work, but no guarantee here. (Btw. there is no guarantee anywhere in this code, according to my GPLv2 license). @@ -19,3 +19,8 @@ Currently, the template is for the STM32F407VEx controllers which have 512k of F The Makefile expects a ``arm-none-eabi-gcc`` which has to be available in the PATH. For most linux users this should work fine. +# Adaptations + +* Memory regions (Flash and RAM sizes and locations) can be adapted in the linker script. +* Stack and Heap reserved areas are also defined in the linkerscript. +* The compiler flags force newlib to rely on external system calls. When using malloc(), printf() etc. you will get errors regarding missing syscalls like ``_sbrk()`` etc. I will add a basic systemcll file in future. But for now you have to implement them yourself.