SWRA657 June 2020 CC3100 , CC3200
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SimpleLink Wi-Fi CC3100, CC3200 Serial Flash
- Trademarks
- 1 Introduction
- 2 How File System Content Gets to the Serial Flash
- 3 File System Guidelines
- 4 User File Mathematics
- 5 System and Configuration Files
- 6 Implementing File System Features From Host Processor
- 7 Factors to Consider in Designing With Serial Flash
- 8 Design Recommendations for Ensuring the Integrity of the Power Supply to the Serial Flash
- 9 Recommended Best Practices
- 10 Implications of Data Integrity Compromise to CC3100/CC3200
- 11 References
4 User File Mathematics
To make use of the file system to store files, it is essential to be able to accurately calculate the occupied memory space per file. The total occupied size on flash is a function of the file content length (or the maximum size upon creation), file attributes and file system metadata.
Figure 1 describes the process for calculating how much memory is actually consumed on the serial flash.
Figure 1. File Size Calculations Table 2. File Size Allocation on Flash
| File Size (bytes) | Page Size | Round to Page | Add Header and Round to Block | Allocated Size via sl_FsGetInfo() |
|---|---|---|---|---|
| 10 | 256 | 256 (1 page) | 4096 (1 block) | 3656 |
| 250000 | 1024 | 250880 (245 pages) | 253952 (62 blocks) | 253512 |
| 1000000 | 4096 | 1003520 (245 pages) | 1007616 (246 blocks) | 10007176 |