Updated the readme with how to start

Author: itzandroidtab

Readme.md

@@ -1,8 +1,41 @@
-# Flash loader template 
-Flash loader template without the need for a Keil/Segger DSK license. Uses Cmake and arm-none-eabi. Uses parts of [klib](https://github.com/itzandroidtab/klib/)
+# Open Flash loader template (OFL)
+Flash loader template without the need for a Keil/Segger DSK license. OFL uses Cmake and arm-none-eabi to build. OFL Uses parts of [klib](https://github.com/itzandroidtab/klib/)
 
-## Targets of this project
-Compatible with Segger J-link (Rip Open flash loader (OFL))
+## Create a Flash loader executable
+To create a OFL executable you need the following:
+* A driver for the peripheral the memory is connected to
+* A driver to communicate with the flash memory
+* Way to feed the watchdog if enabled
+* A way to restore modified registers after deinit
+
+## Stack usage
+In the previous documentation Segger reserved 256 bytes of stack for Open flash loaders. In newer versions the documentation mention 512 bytes of stack with a fallback to 256 bytes for devices with low amounts of memory (debugging linkerscript is set to 256 bytes of stack). 
+
+## Create a flash loader xml file
+SEGGER J-Link uses xml files to add support for external loaders. The xml file configures the follwing:
+* The target Microcontroller for the loader
+* The address the memory is located
+* What executable file to load
+* The name it shows up as in the J-Link software
+
+Example xml file for the LPC1756 is25lq040b open flash loader.
+```xml
+<DataBase>
+    <Device>
+        <ChipInfo Vendor="NXP" Name="LPC1756" />
+        <FlashBankInfo Name="NOR Flash" BaseAddr="0xA0000000">
+            <LoaderInfo Name="SPI flash loader" MaxSize="0x01000000" Loader="flash_loader.elf" LoaderType="FLASH_ALGO_TYPE_OPEN" />
+        </FlashBankInfo>
+    </Device>
+</DataBase>
+```
+
+More info can be found at https://wiki.segger.com/J-Link_Device_Support_Kit
+
+## Installing your open flash loader
+There are 2 ways to install your open flash loader
+1. Manually copying the executable and xml to `%appdata%/SEGGER/JlinkDevices/vendor/device_family`
+2. Using a installer (like [ofl_installer](https://github.com/itzandroidtab/ofl_installer))
 
 ## Example
 A example is available for the [LPC1756 and is25lq040b](https://github.com/itzandroidtab/ofl_lpc1756_is25lq040b). Made using the drivers from: [klib](https://github.com/itzandroidtab/klib).

example.xml

@@ -0,0 +1,8 @@
+<DataBase>
+    <Device>
+        <ChipInfo Vendor="NXP" Name="LPC1756" />
+        <FlashBankInfo Name="NOR Flash" BaseAddr="0xA0000000">
+            <LoaderInfo Name="SPI flash loader" MaxSize="0x01000000" Loader="flash_loader.elf" LoaderType="FLASH_ALGO_TYPE_OPEN" />
+        </FlashBankInfo>
+    </Device>
+</DataBase>