# NET OS FLASH MAP **URL:** \ **Category:** NET+OS\ **Tags:** flash-size, netos, 9210\ **Created:** [February 17, 2015, 11:30am UTC](https://forums.digi.com/t/net-os-flash-map/14385 "2015-02-17T11:30:33Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![gavello](https://avatars.discourse-cdn.com/v4/letter/g/ccd318/32.png) [@gavello](https://forums.digi.com/u/gavello)\ **Post date:** [February 17, 2015, 11:30am UTC](https://forums.digi.com/t/net-os-flash-map/14385/1 "2015-02-17T11:30:33Z")
I need to assign as much flash file system space compiled image.bin results are Compressing blram.bin to blram.bin.compressed Using LZSS Encoder/Decode (v2) Input bytes: 73424 Output bytes: 38685 Compression ratio: 48% Generating header.bin from blram.bin.compressed for BOOT header Image Type: Compressed Image Size: 38685 Flash Offset: 0x0 RAM Address: 0x0 Backup Image Address: 0x0 Assembling blram.s \*\* Save bsp targets in project Finished Building Bsp Building target: image.bin Compressing image.uncompressed to image.uncompressed.compressed Using LZSS Encoder/Decode (v2) Input bytes: 1044160 Output bytes: 641705 Compression ratio: 39% Generating image.bin from image.uncompressed.compressed for BOOT header Image Type: Compressed Image Size: 641705 Flash Offset: 0x10000 RAM Address: 0x4000 Backup Image Address: 0x50150000 Finished building: image.bin under project properties flash memory map I set total flash size to 4M as my module is 9210 4/8 now how do I decide how to set up the other variables appropriately? Backup Image ? File System size Application size? ---
**Author:** ![dakotas\_dad](https://avatars.discourse-cdn.com/v4/letter/d/a88e57/32.png) [@dakotas\_dad](https://forums.digi.com/u/dakotas_dad)\ **Post date:** [February 17, 2015, 12:17pm UTC](https://forums.digi.com/t/net-os-flash-map/14385/2 "2015-02-17T12:17:14Z")
Hello ``` I am not sure I understand the question. In the Flash Memory Map is a set of sliders. You can slide them back and forth. The S/W ensures that you do not go over 4MB. You must, of course remember the following: NVRAM takes up 64KB. This is non-negotiable. The boot loader (unless modified) takes up 64KB. This is non-negotiable. If you do not want a backup image, set it to 0. I believe by default, any FLASH space NOT taken up by the application, the bootloader, the backup image, NVRAM is given to the file system. ``` What else do you need? ---
**Author:** ![gavello](https://avatars.discourse-cdn.com/v4/letter/g/ccd318/32.png) [@gavello](https://forums.digi.com/u/gavello)\ **Post date:** [February 17, 2015, 12:42pm UTC](https://forums.digi.com/t/net-os-flash-map/14385/3 "2015-02-17T12:42:28Z")
I don’t see the default behavior you describe. if slider is set to 1024K I get that not more. Since I need to maximize flash file system storage available I wolud know how to properly set the application and backup dimensions. I see customize.Idr is where variables are set APP\_MAX\_SIZE\_IN\_FLASH 1280K FILE\_SYSTEM\_SIZE 2176K BACKUP\_RECOVERY\_MAX\_SIZE\_IN\_FLASH 448K ---
**Author:** ![dakotas\_dad](https://avatars.discourse-cdn.com/v4/letter/d/a88e57/32.png) [@dakotas\_dad](https://forums.digi.com/u/dakotas_dad)\ **Post date:** [February 17, 2015, 12:55pm UTC](https://forums.digi.com/t/net-os-flash-map/14385/4 "2015-02-17T12:55:49Z")
Yes I had not used the slider in a while. As you increase the size of the file system, the slider decreases the size of unused space, up to the 4MB limit. Further you are correct that ultimately, the slider updates the file customize.ldr. You have the option of directly updating customize.ldr, but we recommend using the slider. The output from the build tells you the size of the application and the backup application. So, MAX\_FLASH\_file\_system\_size = (Total\_FLASH\_space - (bootloader\_size + NVRAM\_size, + application\_image\_size + backup\_image\_size)) ---
**Author:** ![gavello](https://avatars.discourse-cdn.com/v4/letter/g/ccd318/32.png) [@gavello](https://forums.digi.com/u/gavello)\ **Post date:** [February 17, 2015, 1:16pm UTC](https://forums.digi.com/t/net-os-flash-map/14385/5 "2015-02-17T13:16:53Z")
OK thanks one last doubt Using the sliders minimum value is 64K you said that if no backup image is desired (I would read something about how backup image can be used do you have a document?) I could set it to 0 but as I said min with sliders is 64K can i safely write BACKUP\_RECOVERY\_MAX\_SIZE\_IN\_FLASH 0 ? or it has to be 64K Compressed Image Size: 641705 the closest value I can get is 760000 that is the size I have to use for application image? ---
**Author:** ![dakotas\_dad](https://avatars.discourse-cdn.com/v4/letter/d/a88e57/32.png) [@dakotas\_dad](https://forums.digi.com/u/dakotas_dad)\ **Post date:** [February 17, 2015, 1:29pm UTC](https://forums.digi.com/t/net-os-flash-map/14385/6 "2015-02-17T13:29:10Z")
The backup image is used by the bootloader in cases where your primary application becomes corrupt. Before running the primary image the bootloader calculates a CRC for the image. if the CRC does not agree with the CRC in the header, the image is considered corrupt. IN that case, the backup image is run. Generally you want the backup image include the FTP server, so you can reload your primary image. It is optional. I believe in customer.ldr you can set the size of the backup image to 0, assuming that is what you want. What you do with this is application specific. I believe the answer is similar for the application size. It is possible that the granularity in using the sliders is large. To set sizes with a finer granularity directly update customize.ldr.